diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index cf3be87d..ea0a240a 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -36,6 +36,13 @@ jobs:
         run: |
           echo "COMPANION_URL=${{ secrets.COMPANION_URL }}" > .env
           echo "BACKEND_URL=${{ secrets.BACKEND_URL }}" >> .env
+          # Health-data contribution (full on-device DB upload) is OFF for
+          # every build we distribute, sideload included — matching
+          # PRIVACY.md's "we do not collect your data". Passed explicitly
+          # (not just relying on kHealthDataContributionEnabled's default)
+          # so this is true by construction of the CI config itself, not
+          # contingent on nobody ever changing that default later.
+          echo "ENABLE_HEALTH_DATA_CONTRIBUTION=false" >> .env
 
       # Decode the release keystore from a secret. The gradle config picks these
       # env vars up (ANDROID_KEYSTORE_PATH etc.) and signs the release build.
@@ -127,6 +134,13 @@ jobs:
         run: |
           echo "COMPANION_URL=${{ secrets.COMPANION_URL }}" > .env
           echo "BACKEND_URL=${{ secrets.BACKEND_URL }}" >> .env
+          # Health-data contribution (full on-device DB upload) is OFF for
+          # every build we distribute, sideload included — matching
+          # PRIVACY.md's "we do not collect your data". Passed explicitly
+          # (not just relying on kHealthDataContributionEnabled's default)
+          # so this is true by construction of the CI config itself, not
+          # contingent on nobody ever changing that default later.
+          echo "ENABLE_HEALTH_DATA_CONTRIBUTION=false" >> .env
 
       - name: Install flutterfire (required by Crashlytics Xcode build phase)
         run: dart pub global activate flutterfire_cli 1.4.0
diff --git a/NOTICE.md b/NOTICE.md
new file mode 100644
index 00000000..97c3ad5d
--- /dev/null
+++ b/NOTICE.md
@@ -0,0 +1,11 @@
+# Notice
+
+Edge is an independent, open-source project (MIT License — see `LICENSE`). It
+is not affiliated with, sponsored by, or endorsed by WHOOP, Inc. or any of its
+trademarks.
+
+No WHOOP source code, binaries, firmware, or copyrighted assets are included
+in this repository. The Bluetooth protocol support in this project was
+independently developed by observing the band's own Bluetooth communications;
+see [the protocol repo's README](https://github.com/OpenStrap/protocol) for
+methodology notes.
diff --git a/PRIVACY.md b/PRIVACY.md
new file mode 100644
index 00000000..f1430749
--- /dev/null
+++ b/PRIVACY.md
@@ -0,0 +1,87 @@
+# Privacy Policy — Edge / OpenStrap
+
+_Last updated: July 18, 2026_
+
+Edge ("the App") is an independent, open-source project. It is not affiliated
+with, sponsored by, or endorsed by WHOOP, Inc.
+
+**We do not collect your data**
+This section describes every build we ourselves distribute — the signed
+Android APK and iOS IPA published on GitHub Releases, and any future App
+Store/Play Store submission. Your biometric/health data from your paired
+WHOOP 4.0 band — heart rate, heart rate variability (RR intervals), motion
+(accelerometer), raw skin-temperature/blood-oxygen sensor channels, and (if
+you record workouts) GPS location during those workouts — is processed and
+stored entirely on your device in every one of those builds. We do not
+upload it, we do not operate a backend that receives it, and we never see it
+— *unless you separately choose to enable AI Coach or Health app
+integration, described below, which send specific data to services you
+configure.*
+
+Edge is open source. The underlying code contains an off-by-default,
+compile-time flag (`kHealthDataContributionEnabled`, see
+`lib/telemetry/health_uploader.dart`) that an independent developer could
+enable in their *own*, separately-built and separately-distributed copy of
+the app, pointed at a backend of their own choosing. No build we publish
+enables it — our CI explicitly forces it off for every release (see
+`.github/workflows/build.yml`) rather than relying on the flag's default. A
+self-built copy compiled with that flag on is that builder's own software
+and their own responsibility; it is not covered by this policy.
+
+**Anonymous diagnostics (on by default)**
+In every build we distribute, the only thing the App sends off your device
+*automatically* — aside from the optional, user-initiated integrations
+described next — is basic crash/error and performance monitoring, via
+Firebase (Google) — Crashlytics, Performance Monitoring, and Analytics. This
+is on by default; you can turn it off at any
+time in Settings ("Send anonymous diagnostics"), which stops any further
+collection immediately. It never includes your health data — only crash
+reports, basic device info (OS/model/app version), and coarse performance
+timing. This data is handled under Firebase's own privacy and security
+practices, not a system we built or operate ourselves — see Google's Firebase
+privacy & security documentation: https://firebase.google.com/support/privacy.
+
+**Optional, user-initiated integrations**
+If you choose to enable them, the App can also send data to services *you*
+configure:
+- **AI Coach** — if you enable this feature and supply your own API key,
+  summaries of your data are sent to the AI provider you configure (by
+  default, OpenAI) to generate coaching responses. Off by default and
+  requires your own API key.
+- **Health app integration** — if you enable it, the App can write derived
+  daily metrics to Apple Health or Google Health Connect, which are controlled
+  by your device's own OS-level health app, not by us.
+
+**What we don't do**
+We do not sell your data. We do not send your health data to WHOOP, Inc. or
+any advertising network. We do not require a WHOOP account or credentials to
+use the App. We do not operate a backend that stores your health data.
+
+**Your controls**
+Turn off "Send anonymous diagnostics" at any time in Settings — this stops any
+further collection immediately. You can also disable AI Coach or Health app
+integration at any time in Settings if you'd previously turned them on.
+
+Uninstalling the App deletes all of your locally stored data immediately.
+That's the whole picture *unless* you had separately enabled one of the
+optional integrations above — in that case, uninstalling stops the App from
+sending anything further, but does not reach back and delete data already
+sent:
+- Anonymous diagnostics already sent to Firebase are retained and governed by
+  Firebase's own practices (linked above), not by us.
+- Data already sent to your configured AI Coach provider (e.g. OpenAI) is
+  retained and governed by that provider's own policies, not by us.
+- Metrics already written to Apple Health or Google Health Connect are
+  retained and governed by that platform's own data controls, not by us —
+  manage or delete them from that app directly.
+
+**Children**
+This App is not directed to children under 13 (or the relevant age of digital
+consent in your jurisdiction) and we do not knowingly collect data from them.
+
+**Changes**
+We may update this policy; material changes will be reflected here with an
+updated date.
+
+**Contact**
+Questions about this policy: abdulsaheel81@gmail.com.
diff --git a/docs/privacy.html b/docs/privacy.html
index c4791acb..2196718c 100644
--- a/docs/privacy.html
+++ b/docs/privacy.html
@@ -26,26 +26,51 @@ <h1>Privacy Policy — Edge / OpenStrap</h1>
     <p>Edge ("the App") is an independent, open-source project. It is not affiliated
       with, sponsored by, or endorsed by WHOOP, Inc.</p>
 
-    <h2>Data we collect</h2>
-    <ul>
-      <li>Biometric/health data from your paired WHOOP 4.0 band over Bluetooth: heart
-        rate, heart rate variability (RR intervals), motion (accelerometer), raw
-        skin-temperature/blood-oxygen sensor channels, and (if you record workouts) GPS
-        location during those workouts.</li>
-      <li>Basic app usage/crash telemetry, only if you opt in.</li>
-    </ul>
+    <h2>We do not collect your data</h2>
+    <p>This section describes every build we ourselves distribute — the signed
+      Android APK and iOS IPA published on GitHub Releases, and any future App
+      Store/Play Store submission. Your biometric/health data from your paired
+      WHOOP 4.0 band — heart rate, heart rate variability (RR intervals), motion
+      (accelerometer), raw skin-temperature/blood-oxygen sensor channels, and (if
+      you record workouts) GPS location during those workouts — is processed and
+      stored entirely on your device in every one of those builds. We do not
+      upload it, we do not operate a backend that receives it, and we never see
+      it — <em>unless you separately choose to enable AI Coach or Health app
+      integration, described below, which send specific data to services you
+      configure.</em></p>
+
+    <p>Edge is open source. The underlying code contains an off-by-default,
+      compile-time flag (<code>kHealthDataContributionEnabled</code>) that an
+      independent developer could enable in their <em>own</em>, separately-built
+      and separately-distributed copy of the app, pointed at a backend of their
+      own choosing. No build we publish enables it — our CI explicitly forces it
+      off for every release rather than relying on the flag's default. A
+      self-built copy compiled with that flag on is that builder's own software
+      and their own responsibility; it is not covered by this policy.</p>
+
+    <h2>Anonymous diagnostics (on by default)</h2>
+    <p>In every build we distribute, the only thing the App sends off your device
+      <em>automatically</em> — aside from the optional, user-initiated
+      integrations described next — is basic crash/error and performance
+      monitoring, via Firebase (Google) — Crashlytics, Performance Monitoring, and
+      Analytics. This is on by default; you can turn it off at any time in
+      Settings ("Send anonymous diagnostics"),
+      which stops any further collection immediately. It never includes your
+      health data — only crash
+      reports, basic device info (OS/model/app version), and coarse performance
+      timing. This data is handled under Firebase's own privacy and security
+      practices, not a system we built or operate ourselves — see Google's Firebase
+      privacy &amp; security documentation:
+      <a href="https://firebase.google.com/support/privacy">firebase.google.com/support/privacy</a>.</p>
 
-    <h2>Where your data lives</h2>
-    <p>By default, all of the above is stored locally on your device only. We do not
-      upload it anywhere unless you explicitly opt in to one of the following:</p>
+    <h2>Optional, user-initiated integrations</h2>
+    <p>If you choose to enable them, the App can also send data to services
+      <em>you</em> configure:</p>
     <ul>
-      <li><strong>Cloud backup</strong> — a one-time or periodic encrypted upload of
-        your local database to our own backend, only if you turn this on in
-        Settings.</li>
       <li><strong>AI Coach</strong> — if you enable this feature and supply your own
         API key, summaries of your data are sent to the AI provider you configure (by
-        default, OpenAI) to generate coaching responses. This is off by default and
-        requires your own API key.</li>
+        default, OpenAI) to generate coaching responses. Off by default and requires
+        your own API key.</li>
       <li><strong>Health app integration</strong> — if you enable it, the App can
         write derived daily metrics to Apple Health or Google Health Connect, which
         are controlled by your device's own OS-level health app, not by us.</li>
@@ -54,18 +79,28 @@ <h2>Where your data lives</h2>
     <h2>What we don't do</h2>
     <p>We do not sell your data. We do not send your health data to WHOOP, Inc. or any
       advertising network. We do not require a WHOOP account or credentials to use the
-      App.</p>
+      App. We do not operate a backend that stores your health data.</p>
 
     <h2>Your controls</h2>
-    <p>You can disable cloud backup, telemetry, or AI Coach at any time in Settings.
-      Uninstalling the App deletes all of its local data from your device — there is
-      no separate local-data export left behind. In-app, Settings → "Reset profile"
-      clears your local profile (name, age, body metrics) and forgets your paired
-      band, but does not delete your previously stored band data on the device; full
-      local deletion currently requires uninstalling the App. If you opted in to
-      cloud backup, we do not yet have a self-serve deletion flow for that uploaded
-      copy — email us at <a href="mailto:abdulsaheel81@gmail.com">abdulsaheel81@gmail.com</a> to
-      request its deletion and we will process it manually.</p>
+    <p>Turn off "Send anonymous diagnostics" at any time in Settings — this stops any
+      further collection immediately. You can also disable AI Coach or Health app
+      integration at any time in Settings if you'd previously turned them on.</p>
+
+    <p>Uninstalling the App deletes all of your locally stored data immediately.
+      That's the whole picture <em>unless</em> you had separately enabled one of
+      the optional integrations above — in that case, uninstalling stops the App
+      from sending anything further, but does not reach back and delete data
+      already sent:</p>
+    <ul>
+      <li>Anonymous diagnostics already sent to Firebase are retained and
+        governed by Firebase's own practices (linked above), not by us.</li>
+      <li>Data already sent to your configured AI Coach provider (e.g. OpenAI)
+        is retained and governed by that provider's own policies, not by
+        us.</li>
+      <li>Metrics already written to Apple Health or Google Health Connect are
+        retained and governed by that platform's own data controls, not by us
+        — manage or delete them from that app directly.</li>
+    </ul>
 
     <h2>Children</h2>
     <p>This App is not directed to children under 13 (or the relevant age of digital
diff --git a/docs/terms.html b/docs/terms.html
index be56a716..9d548cc4 100644
--- a/docs/terms.html
+++ b/docs/terms.html
@@ -62,10 +62,13 @@ <h2>5. Your Responsibilities</h2>
     </ul>
 
     <h2>6. Third-Party Services</h2>
-    <p>Certain optional features rely on third-party services you separately
+    <p>The App uses Firebase (Google) for anonymous crash/error and performance
+      monitoring (Crashlytics, Performance Monitoring, Analytics). This is on by
+      default and can be turned off at any time in Settings — see the Privacy
+      Policy for details. It never includes your health data.</p>
+    <p>Certain other, optional features rely on third-party services you separately
       configure or consent to, including:</p>
     <ul>
-      <li>An optional cloud backup feature, self-hosted by the App's maintainers.</li>
       <li>An optional AI Coach feature, which sends data you choose to share to a
         third-party AI provider (by default, OpenAI) using an API key you
         supply.</li>
diff --git a/guides/IOS_INSTALLATION.md b/guides/IOS_INSTALLATION.md
index 8bb1ed47..f3b663fe 100644
--- a/guides/IOS_INSTALLATION.md
+++ b/guides/IOS_INSTALLATION.md
@@ -126,6 +126,26 @@ For a signed release-style device install:
 flutter run --release -d <device-id> --dart-define-from-file=.env
 ```
 
+## Version Numbers
+
+`Runner` tracks `pubspec.yaml`'s `version:` automatically via `Info.plist`'s
+`CFBundleShortVersionString`/`CFBundleVersion` keys, which point at
+`$(FLUTTER_BUILD_NAME)`/`$(FLUTTER_BUILD_NUMBER)` (Flutter writes these into
+`ios/Flutter/Generated.xcconfig` on every build). Runner's own
+`CURRENT_PROJECT_VERSION` build setting also resolves to `$(FLUTTER_BUILD_NUMBER)`;
+it does not set a `MARKETING_VERSION` build setting at all — the marketing
+version comes solely from the `Info.plist` key above.
+
+The **`OpenStrapWidget`/`OpenStrapWidgetExtension`** and **`OpenStrapWatch Watch
+App`** targets are NOT wired to that mechanism — they don't include
+`Generated.xcconfig`, so those Flutter variables aren't available to them, and
+`MARKETING_VERSION`/`CURRENT_PROJECT_VERSION` are hardcoded per-target in
+`project.pbxproj` instead. **Bump these by hand to match `pubspec.yaml`'s
+`version:` every time it changes** — App Store Connect validates that a host
+app's embedded extensions and companion Watch app carry compatible version
+numbers, so letting these drift is a real upload-time risk, not just cosmetic
+inconsistency.
+
 ## Debug Builds and Home-Screen Relaunch
 
 Flutter debug builds on iOS must be launched by Flutter tooling or Xcode. If you
diff --git a/ios/Runner.xcodeproj/project.pbxproj b/ios/Runner.xcodeproj/project.pbxproj
index 4329a129..bee5ce53 100644
--- a/ios/Runner.xcodeproj/project.pbxproj
+++ b/ios/Runner.xcodeproj/project.pbxproj
@@ -18,7 +18,6 @@
 		5348973F2FDC19C80033A4D9 /* SwiftUI.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 5348973E2FDC19C80033A4D9 /* SwiftUI.framework */; };
 		5348974E2FDC19C90033A4D9 /* OpenStrapWidgetExtension.appex in Embed Foundation Extensions */ = {isa = PBXBuildFile; fileRef = 5348973B2FDC19C80033A4D9 /* OpenStrapWidgetExtension.appex */; settings = {ATTRIBUTES = (RemoveHeadersOnCopy, ); }; };
 		534897A72FDC2B310033A4D9 /* LiveActivityBridge.swift in Sources */ = {isa = PBXBuildFile; fileRef = 534897A62FDC2B310033A4D9 /* LiveActivityBridge.swift */; };
-		BEEF00000000000000000002 /* BreathingLiveActivityBridge.swift in Sources */ = {isa = PBXBuildFile; fileRef = BEEF00000000000000000001 /* BreathingLiveActivityBridge.swift */; };
 		53962E962FF6EE120061A61B /* WatchBridge.swift in Sources */ = {isa = PBXBuildFile; fileRef = 53962E952FF6EE120061A61B /* WatchBridge.swift */; };
 		53962E972FF6EE120061A61B /* OpenStrapIntents.swift in Sources */ = {isa = PBXBuildFile; fileRef = 53962E942FF6EE120061A61B /* OpenStrapIntents.swift */; };
 		630172CC9317145AD5F8F3B7 /* Pods_RunnerTests.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 2C721EA0C8D31A3834E66203 /* Pods_RunnerTests.framework */; };
@@ -28,6 +27,7 @@
 		97C146FE1CF9000F007C117D /* Assets.xcassets in Resources */ = {isa = PBXBuildFile; fileRef = 97C146FD1CF9000F007C117D /* Assets.xcassets */; };
 		97C147011CF9000F007C117D /* LaunchScreen.storyboard in Resources */ = {isa = PBXBuildFile; fileRef = 97C146FF1CF9000F007C117D /* LaunchScreen.storyboard */; };
 		ACCE55E7000000000000B11D /* AccessorySetup.swift in Sources */ = {isa = PBXBuildFile; fileRef = ACCE55E7000000000000F11E /* AccessorySetup.swift */; };
+		BEEF00000000000000000002 /* BreathingLiveActivityBridge.swift in Sources */ = {isa = PBXBuildFile; fileRef = BEEF00000000000000000001 /* BreathingLiveActivityBridge.swift */; };
 		FADE0001FADE0001FADE0001 /* OpenStrapWatch Watch App.app in Embed Watch Content */ = {isa = PBXBuildFile; fileRef = 53962EBE2FF6EF790061A61B /* OpenStrapWatch Watch App.app */; settings = {ATTRIBUTES = (RemoveHeadersOnCopy, ); }; };
 /* End PBXBuildFile section */
 
@@ -105,7 +105,6 @@
 		534897562FDC1A450033A4D9 /* Runner.entitlements */ = {isa = PBXFileReference; lastKnownFileType = text.plist.entitlements; path = Runner.entitlements; sourceTree = "<group>"; };
 		534897572FDC1A610033A4D9 /* OpenStrapWidgetExtension.entitlements */ = {isa = PBXFileReference; lastKnownFileType = text.plist.entitlements; path = OpenStrapWidgetExtension.entitlements; sourceTree = "<group>"; };
 		534897A62FDC2B310033A4D9 /* LiveActivityBridge.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = LiveActivityBridge.swift; sourceTree = "<group>"; };
-		BEEF00000000000000000001 /* BreathingLiveActivityBridge.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = BreathingLiveActivityBridge.swift; sourceTree = "<group>"; };
 		53962E942FF6EE120061A61B /* OpenStrapIntents.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = OpenStrapIntents.swift; sourceTree = "<group>"; };
 		53962E952FF6EE120061A61B /* WatchBridge.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = WatchBridge.swift; sourceTree = "<group>"; };
 		53962EBE2FF6EF790061A61B /* OpenStrapWatch Watch App.app */ = {isa = PBXFileReference; explicitFileType = wrapper.application; includeInIndex = 0; path = "OpenStrapWatch Watch App.app"; sourceTree = BUILT_PRODUCTS_DIR; };
@@ -128,6 +127,7 @@
 		97C147021CF9000F007C117D /* Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
 		ACCE55E7000000000000F11E /* AccessorySetup.swift */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = sourcecode.swift; path = AccessorySetup.swift; sourceTree = "<group>"; };
 		B0B95B9F07C8083A2DB92078 /* Pods-RunnerTests.debug.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-RunnerTests.debug.xcconfig"; path = "Target Support Files/Pods-RunnerTests/Pods-RunnerTests.debug.xcconfig"; sourceTree = "<group>"; };
+		BEEF00000000000000000001 /* BreathingLiveActivityBridge.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = BreathingLiveActivityBridge.swift; sourceTree = "<group>"; };
 		DE1829A4D85DB1C3222C2CB5 /* Pods-RunnerTests.release.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-RunnerTests.release.xcconfig"; path = "Target Support Files/Pods-RunnerTests/Pods-RunnerTests.release.xcconfig"; sourceTree = "<group>"; };
 		EC2DC396945E3B2DAA52EB3F /* Pods-RunnerTests.profile.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-RunnerTests.profile.xcconfig"; path = "Target Support Files/Pods-RunnerTests/Pods-RunnerTests.profile.xcconfig"; sourceTree = "<group>"; };
 		FE8EE10565E740E87BE6E423 /* Pods-Runner.profile.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-Runner.profile.xcconfig"; path = "Target Support Files/Pods-Runner/Pods-Runner.profile.xcconfig"; sourceTree = "<group>"; };
@@ -833,7 +833,7 @@
 				CLANG_WARN_UNGUARDED_AVAILABILITY = YES_AGGRESSIVE;
 				CODE_SIGN_ENTITLEMENTS = OpenStrapWidgetExtension.entitlements;
 				CODE_SIGN_STYLE = Automatic;
-				CURRENT_PROJECT_VERSION = 1;
+				CURRENT_PROJECT_VERSION = 47;
 				DEVELOPMENT_TEAM = "$(APPLE_DEVELOPMENT_TEAM)";
 				ENABLE_USER_SCRIPT_SANDBOXING = YES;
 				GCC_C_LANGUAGE_STANDARD = gnu17;
@@ -849,7 +849,7 @@
 					"@executable_path/../../Frameworks",
 				);
 				LOCALIZATION_PREFERS_STRING_CATALOGS = YES;
-				MARKETING_VERSION = 1.0;
+				MARKETING_VERSION = 0.9.14;
 				MTL_ENABLE_DEBUG_INFO = INCLUDE_SOURCE;
 				MTL_FAST_MATH = YES;
 				PRODUCT_BUNDLE_IDENTIFIER = "$(APP_WIDGET_BUNDLE_IDENTIFIER)";
@@ -880,7 +880,7 @@
 				CLANG_WARN_UNGUARDED_AVAILABILITY = YES_AGGRESSIVE;
 				CODE_SIGN_ENTITLEMENTS = OpenStrapWidgetExtension.entitlements;
 				CODE_SIGN_STYLE = Automatic;
-				CURRENT_PROJECT_VERSION = 1;
+				CURRENT_PROJECT_VERSION = 47;
 				DEVELOPMENT_TEAM = "$(APPLE_DEVELOPMENT_TEAM)";
 				ENABLE_USER_SCRIPT_SANDBOXING = YES;
 				GCC_C_LANGUAGE_STANDARD = gnu17;
@@ -896,7 +896,7 @@
 					"@executable_path/../../Frameworks",
 				);
 				LOCALIZATION_PREFERS_STRING_CATALOGS = YES;
-				MARKETING_VERSION = 1.0;
+				MARKETING_VERSION = 0.9.14;
 				MTL_FAST_MATH = YES;
 				PRODUCT_BUNDLE_IDENTIFIER = "$(APP_WIDGET_BUNDLE_IDENTIFIER)";
 				PRODUCT_NAME = "$(TARGET_NAME)";
@@ -924,7 +924,7 @@
 				CLANG_WARN_UNGUARDED_AVAILABILITY = YES_AGGRESSIVE;
 				CODE_SIGN_ENTITLEMENTS = OpenStrapWidgetExtension.entitlements;
 				CODE_SIGN_STYLE = Automatic;
-				CURRENT_PROJECT_VERSION = 1;
+				CURRENT_PROJECT_VERSION = 47;
 				DEVELOPMENT_TEAM = "$(APPLE_DEVELOPMENT_TEAM)";
 				ENABLE_USER_SCRIPT_SANDBOXING = YES;
 				GCC_C_LANGUAGE_STANDARD = gnu17;
@@ -940,7 +940,7 @@
 					"@executable_path/../../Frameworks",
 				);
 				LOCALIZATION_PREFERS_STRING_CATALOGS = YES;
-				MARKETING_VERSION = 1.0;
+				MARKETING_VERSION = 0.9.14;
 				MTL_FAST_MATH = YES;
 				PRODUCT_BUNDLE_IDENTIFIER = "$(APP_WIDGET_BUNDLE_IDENTIFIER)";
 				PRODUCT_NAME = "$(TARGET_NAME)";
@@ -971,8 +971,8 @@
 				CODE_SIGN_ENTITLEMENTS = "OpenStrapWatch Watch App/OpenStrapWatch Watch App.entitlements";
 				CODE_SIGN_IDENTITY = "Apple Development";
 				CODE_SIGN_STYLE = Automatic;
-				CURRENT_PROJECT_VERSION = 17;
-				DEVELOPMENT_TEAM = 2U62X3RF3R;
+				CURRENT_PROJECT_VERSION = 47;
+				DEVELOPMENT_TEAM = "$(APPLE_DEVELOPMENT_TEAM)";
 				ENABLE_PREVIEWS = YES;
 				ENABLE_USER_SCRIPT_SANDBOXING = YES;
 				GCC_C_LANGUAGE_STANDARD = gnu17;
@@ -987,7 +987,7 @@
 					"@executable_path/Frameworks",
 				);
 				LOCALIZATION_PREFERS_STRING_CATALOGS = YES;
-				MARKETING_VERSION = 0.7.0;
+				MARKETING_VERSION = 0.9.14;
 				MTL_ENABLE_DEBUG_INFO = INCLUDE_SOURCE;
 				MTL_FAST_MATH = YES;
 				PRODUCT_BUNDLE_IDENTIFIER = "$(APP_BUNDLE_IDENTIFIER).watchkitapp";
@@ -1026,8 +1026,8 @@
 				CLANG_WARN_UNGUARDED_AVAILABILITY = YES_AGGRESSIVE;
 				CODE_SIGN_ENTITLEMENTS = "OpenStrapWatch Watch App/OpenStrapWatch Watch App.entitlements";
 				CODE_SIGN_STYLE = Automatic;
-				CURRENT_PROJECT_VERSION = 17;
-				DEVELOPMENT_TEAM = 2U62X3RF3R;
+				CURRENT_PROJECT_VERSION = 47;
+				DEVELOPMENT_TEAM = "$(APPLE_DEVELOPMENT_TEAM)";
 				ENABLE_PREVIEWS = YES;
 				ENABLE_USER_SCRIPT_SANDBOXING = YES;
 				GCC_C_LANGUAGE_STANDARD = gnu17;
@@ -1042,7 +1042,7 @@
 					"@executable_path/Frameworks",
 				);
 				LOCALIZATION_PREFERS_STRING_CATALOGS = YES;
-				MARKETING_VERSION = 0.7.0;
+				MARKETING_VERSION = 0.9.14;
 				MTL_FAST_MATH = YES;
 				PRODUCT_BUNDLE_IDENTIFIER = "$(APP_BUNDLE_IDENTIFIER).watchkitapp";
 				PRODUCT_NAME = "$(TARGET_NAME)";
@@ -1077,8 +1077,8 @@
 				CLANG_WARN_UNGUARDED_AVAILABILITY = YES_AGGRESSIVE;
 				CODE_SIGN_ENTITLEMENTS = "OpenStrapWatch Watch App/OpenStrapWatch Watch App.entitlements";
 				CODE_SIGN_STYLE = Automatic;
-				CURRENT_PROJECT_VERSION = 17;
-				DEVELOPMENT_TEAM = 2U62X3RF3R;
+				CURRENT_PROJECT_VERSION = 47;
+				DEVELOPMENT_TEAM = "$(APPLE_DEVELOPMENT_TEAM)";
 				ENABLE_PREVIEWS = YES;
 				ENABLE_USER_SCRIPT_SANDBOXING = YES;
 				GCC_C_LANGUAGE_STANDARD = gnu17;
@@ -1093,7 +1093,7 @@
 					"@executable_path/Frameworks",
 				);
 				LOCALIZATION_PREFERS_STRING_CATALOGS = YES;
-				MARKETING_VERSION = 0.7.0;
+				MARKETING_VERSION = 0.9.14;
 				MTL_FAST_MATH = YES;
 				PRODUCT_BUNDLE_IDENTIFIER = "$(APP_BUNDLE_IDENTIFIER).watchkitapp";
 				PRODUCT_NAME = "$(TARGET_NAME)";
diff --git a/ios/Runner/Assets.xcassets/LaunchBackground.colorset/Contents.json b/ios/Runner/Assets.xcassets/LaunchBackground.colorset/Contents.json
new file mode 100644
index 00000000..19292716
--- /dev/null
+++ b/ios/Runner/Assets.xcassets/LaunchBackground.colorset/Contents.json
@@ -0,0 +1,38 @@
+{
+  "colors" : [
+    {
+      "color" : {
+        "color-space" : "srgb",
+        "components" : {
+          "alpha" : "1.000",
+          "blue" : "0xEC",
+          "green" : "0xF1",
+          "red" : "0xF4"
+        }
+      },
+      "idiom" : "universal"
+    },
+    {
+      "appearances" : [
+        {
+          "appearance" : "luminosity",
+          "value" : "dark"
+        }
+      ],
+      "color" : {
+        "color-space" : "srgb",
+        "components" : {
+          "alpha" : "1.000",
+          "blue" : "0x0D",
+          "green" : "0x11",
+          "red" : "0x14"
+        }
+      },
+      "idiom" : "universal"
+    }
+  ],
+  "info" : {
+    "author" : "xcode",
+    "version" : 1
+  }
+}
diff --git a/ios/Runner/Assets.xcassets/LaunchImage.imageset/LaunchImage.png b/ios/Runner/Assets.xcassets/LaunchImage.imageset/LaunchImage.png
index 9da19eac..bf1b93a1 100644
Binary files a/ios/Runner/Assets.xcassets/LaunchImage.imageset/LaunchImage.png and b/ios/Runner/Assets.xcassets/LaunchImage.imageset/LaunchImage.png differ
diff --git a/ios/Runner/Assets.xcassets/LaunchImage.imageset/LaunchImage@2x.png b/ios/Runner/Assets.xcassets/LaunchImage.imageset/LaunchImage@2x.png
index 9da19eac..664f151c 100644
Binary files a/ios/Runner/Assets.xcassets/LaunchImage.imageset/LaunchImage@2x.png and b/ios/Runner/Assets.xcassets/LaunchImage.imageset/LaunchImage@2x.png differ
diff --git a/ios/Runner/Assets.xcassets/LaunchImage.imageset/LaunchImage@3x.png b/ios/Runner/Assets.xcassets/LaunchImage.imageset/LaunchImage@3x.png
index 9da19eac..89f9b6b7 100644
Binary files a/ios/Runner/Assets.xcassets/LaunchImage.imageset/LaunchImage@3x.png and b/ios/Runner/Assets.xcassets/LaunchImage.imageset/LaunchImage@3x.png differ
diff --git a/ios/Runner/Base.lproj/LaunchScreen.storyboard b/ios/Runner/Base.lproj/LaunchScreen.storyboard
index f2e259c7..ad5c6556 100644
--- a/ios/Runner/Base.lproj/LaunchScreen.storyboard
+++ b/ios/Runner/Base.lproj/LaunchScreen.storyboard
@@ -19,7 +19,7 @@
                             <imageView opaque="NO" clipsSubviews="YES" multipleTouchEnabled="YES" contentMode="center" image="LaunchImage" translatesAutoresizingMaskIntoConstraints="NO" id="YRO-k0-Ey4">
                             </imageView>
                         </subviews>
-                        <color key="backgroundColor" red="1" green="1" blue="1" alpha="1" colorSpace="custom" customColorSpace="sRGB"/>
+                        <color key="backgroundColor" name="LaunchBackground"/>
                         <constraints>
                             <constraint firstItem="YRO-k0-Ey4" firstAttribute="centerX" secondItem="Ze5-6b-2t3" secondAttribute="centerX" id="1a2-6s-vTC"/>
                             <constraint firstItem="YRO-k0-Ey4" firstAttribute="centerY" secondItem="Ze5-6b-2t3" secondAttribute="centerY" id="4X2-HB-R7a"/>
@@ -32,6 +32,6 @@
         </scene>
     </scenes>
     <resources>
-        <image name="LaunchImage" width="168" height="185"/>
+        <image name="LaunchImage" width="96" height="96"/>
     </resources>
 </document>
diff --git a/ios/Runner/Info.plist b/ios/Runner/Info.plist
index 524c5da4..2fcc9d28 100644
--- a/ios/Runner/Info.plist
+++ b/ios/Runner/Info.plist
@@ -44,6 +44,21 @@
 	<string>OpenStrap connects to your WHOOP band over Bluetooth to sync your health data.</string>
 	<key>NSLocationWhenInUseUsageDescription</key>
 	<string>OpenStrap records your route on a map during a run, ride or walk so you can see it, colored by heart-rate zone, when the workout ends. Your location stays on this device and is never uploaded.</string>
+	<!-- NSLocationAlwaysAndWhenInUseUsageDescription: not requested by app code
+	     (gps_source.dart sets allowBackgroundLocationUpdates: false, WhenInUse
+	     only — see the UIBackgroundModes comment below). geolocator_apple's
+	     PermissionHandler.m links [CLLocationManager requestAlwaysAuthorization]
+	     unconditionally, which App Store Connect's static binary scan (ITMS-90683)
+	     flags even though that path is never invoked at runtime. -->
+	<key>NSLocationAlwaysAndWhenInUseUsageDescription</key>
+	<string>OpenStrap does not track your location in the background. This permission is linked by a dependency but unused — the app only ever asks for location access while you're actively viewing a workout route.</string>
+	<!-- NSPhotoLibraryUsageDescription: not used by app code — import_screen.dart's
+	     only FilePicker call uses FileType.any (Files app / UIDocumentPicker),
+	     never .image/.media. file_picker's iOS podspec unconditionally bundles
+	     DKImagePickerController/PhotoGallery + DKPhotoGallery, which link
+	     PHPhotoLibrary APIs and trip the same ITMS-90683 static scan. -->
+	<key>NSPhotoLibraryUsageDescription</key>
+	<string>OpenStrap does not access your photo library. This permission is linked by a dependency but unused — importing your own exported WHOOP data uses the Files app, not Photos.</string>
 	<key>NSSupportsLiveActivities</key>
 	<true/>
 	<key>OpenStrapAppGroupIdentifier</key>
diff --git a/lib/compute/crossday_pipeline.dart b/lib/compute/crossday_pipeline.dart
index 5c70e3cb..e3931c95 100644
--- a/lib/compute/crossday_pipeline.dart
+++ b/lib/compute/crossday_pipeline.dart
@@ -222,8 +222,8 @@ Map<String, dynamic> buildCrossDayBundle(
     tsb: ls?.tsb,
   );
 
-  // ── VO₂max + WHOOP-Age (physiological age). Resting VO₂max (Uth HRmax:RHR)
-  //    over the baseline RHR; WHOOP-Age composites VO₂max + RHR + HRV + sleep +
+  // ── VO₂max + Fitness Age (physiological age). Resting VO₂max (Uth HRmax:RHR)
+  //    over the baseline RHR; Fitness Age composites VO₂max + RHR + HRV + sleep +
   //    steps vs age-norms. All ESTIMATE, absent on missing inputs.
   final age = _numOrNull(profile['age']);
   final sexStr = (profile['sex'] as String?)?.toLowerCase();
@@ -301,7 +301,7 @@ Map<String, dynamic> buildCrossDayBundle(
     },
     'strain_coach': strainTgt.toJson((v) => v.toJson()),
     'vo2max': vo2.toJson(),
-    'whoop_age': physAge.toJson((v) => v.toJson()),
+    'fitness_age': physAge.toJson((v) => v.toJson()),
     'percentiles': percentiles,
     'recent': recent,
   };
diff --git a/lib/compute/derivation_engine.dart b/lib/compute/derivation_engine.dart
index 511e337b..c8549ac4 100644
--- a/lib/compute/derivation_engine.dart
+++ b/lib/compute/derivation_engine.dart
@@ -101,7 +101,7 @@ import 'substrate.dart';
 /// also tunes this estimate. Bumping re-derives non-finalized days so they fill.
 // v20: principled nap detection (van Hees immobility + HR-dip) → `naps` block +
 // `nap_min` scalar; cross-day Sleep Coach (need/bedtime/cycle-wake/performance),
-// Strain Coach (recovery-gated target), VO₂max + WHOOP-Age, all in the crossday
+// Strain Coach (recovery-gated target), VO₂max + Fitness Age, all in the crossday
 // bundle.
 // v21: all-day HRV line (`series.hrv_day`, epoch rolling RMSSD over 24/7 RR).
 // v22: all-day RESP line (`series.resp_day`, rolling RSA br/min) + relative
@@ -210,7 +210,28 @@ import 'substrate.dart';
 // over time while per-night-local always leads. Deep stays a low-confidence
 // NREM sub-split (deep_low_confidence). The profile self-seeds across this
 // re-derivation sweep; no explicit migration. Bump so every day re-stages.
-const int kAlgoVersion = 42;
+// v43: readinessComposite now falls back to a mean/SD z when the robust (median
+// +MAD) z is degenerate (MAD==0 on a tightly-clustered quantized baseline —
+// whole-bpm RHR / integer skin-temp ADC), which was intermittently blanking the
+// whole readiness score to "—" on nights that had valid sleep. Bump so days that
+// were previously absent-for-that-reason recompute a real score.
+// v44: two consistency fixes; neither changes a scalar that a previously
+// FINALIZED day_result already had right, but both affect data availability/
+// consistency going forward. (1) A day whose offloaded second-half compute
+// (naps/workouts/HRR/wear/curves/wake-features) failed or timed out — but
+// whose headline scalars (readiness/RHR/RMSSD) already succeeded — could get
+// marked finalized and treated as fully "derived" by the raw-pruning guard,
+// permanently losing the raw substrate needed to ever fill in those missing
+// fields on retry. Now tracked via a new `partial` day_result column and
+// excluded from both age-based finalization and the pruning guard until the
+// second half actually completes. (2) The wake_day_features early-read
+// artifact (what the Today repo shows before the full day result is ready)
+// was copying the pre-hybrid-correction 1Hz-only step/calorie estimate
+// instead of the corrected real-100Hz+1Hz hybrid value computed moments
+// later in the same pass — the final day_result was always correct, only
+// this transient early read was stale. Bump so any day currently sitting
+// non-finalized re-derives with both fixes in effect.
+const int kAlgoVersion = 44;
 
 /// Raw is kept this many days past derivation, then pruned (derived stays).
 const int rawRetentionDays = 3;
@@ -1397,6 +1418,28 @@ class DerivationEngine {
         message: 'readiness_absent',
         context: flat,
       );
+      // Also surface the SURPRISING case — readiness absent when it should NOT
+      // be (adequate inputs, not the honest cold-start `need_baseline` note) —
+      // as a queryable Crashlytics non-fatal, so a residual "readiness '—' even
+      // with sleep present" is diagnosable from the per-input flags WITHOUT GA4
+      // access. Cold-start (need_baseline) absences stay Analytics-only so this
+      // stays low-noise (and, post the MAD/SD-z fallback, rare).
+      final note = (diag['note'] as String?) ?? '';
+      if (!note.startsWith('need_baseline')) {
+        final summary = StringBuffer('readiness_absent');
+        for (final key in ['hrv', 'rhr', 'resp', 'temp']) {
+          final v = (diag[key] as Map?)?.cast<String, dynamic>();
+          if (v == null) continue;
+          summary.write(
+              ' $key=${v['value'] == true ? 'Y' : 'n'}/${v['baseline_n']}');
+        }
+        summary.write(' | $note');
+        TelemetryService.instance.recordNonFatal(
+          StateError(summary.toString()),
+          StackTrace.current,
+          reason: 'readiness_absent',
+        );
+      }
     }
 
     // Where this day's sleep window came from (auto / auto_fallback / manual /
@@ -1405,149 +1448,120 @@ class DerivationEngine {
     bundle['sleep_source'] = day.sleepSource;
 
     final scMap = (bundle['scalars'] as Map?)?.cast<String, dynamic>();
-    final wake = _buildWakeDayFeatures(
-      daySub,
-      profile,
-      sleepOnsetSec: day.sleepOnsetSec,
-      sleepOffsetSec: day.sleepOffsetSec,
-      restingHr: (scMap?['rhr'] as num?)?.toDouble(),
-    );
-    _applyWakeDayFeatures(bundle, scMap, wake);
-
-    // ── STEPS (real 100 Hz + 1 Hz estimate) + TOTAL DAILY ENERGY (TDEE) ───────
-    // Pull the day's 100 Hz coverage windows (device-time sec) + their real step
-    // count so _stepsAndEnergy can prefer them and estimate only the rest.
-    final dayLo = daySub.length == 0 ? 0 : daySub.tsSec.first;
-    final dayHi = daySub.length == 0 ? 0 : daySub.tsSec.last + 60;
-    final coverageWindows = await LocalDb.coverageWindowsOverlapping(
-      dayLo,
-      dayHi,
-    );
-    final liveStepsReal = await LocalDb.liveStepsForDay(day.date);
-    final stepCalib = await LocalDb.getStepCalibration();
-    _stepsAndEnergy(
-      bundle,
-      scMap,
-      daySub,
-      profile,
-      coverageWindows,
-      liveStepsReal,
-      stepCalib,
-    );
 
-    // ── More substrate-derived detail blocks (computed here, where the full
-    //    sliced substrate lives — same pattern as activeMin; these are fresh
-    //    <String,dynamic> blocks so ints are safe, unlike the double? scalars). ─
-    bundle['daytime_hrv'] = _daytimeHrv(
-      daySub,
-      day.sleepOnsetSec,
-      day.sleepOffsetSec,
-    ); // waking RMSSD
-    // ALL-DAY HRV / resp / skin-temp lines for the Timeline graph. Epoch-stamped
-    // (rolling RMSSD, rolling RSA, relative skin-temp) over the day-wide 24/7
-    // substrate RR/ADC — context lines, movement-confounded, not the recovery
-    // values. Computed here where the day substrate lives.
-    final sersMap = (bundle['series'] as Map?)?.cast<String, dynamic>();
-    sersMap?['hrv_day'] = _dayHrvCurve(daySub);
-    sersMap?['resp_day'] = _dayRespCurve(daySub);
-    sersMap?['skin_temp_day'] = _daySkinTempCurve(daySub);
-    bundle['restlessness'] = _restlessness(sleepSub); // nocturnal movement
-    bundle['sleep_periods'] = _sleepPeriods(
-      daySub,
-      day.sleepOnsetSec,
-      day.sleepOffsetSec,
-    ); // naps
-    // Principled daytime NAPS (van Hees immobility + HR-dip): rich per-nap block
-    // + a `nap_min` scalar feeding the Sleep Coach's nap credit + the Timeline.
-    _attachNaps(bundle, scMap, daySub, day.sleepOnsetSec, day.sleepOffsetSec);
-
-    // Per-5-min movement-level curve for the "Your day" Movement view ([{t,v}],
-    // v = fraction of moving seconds 0..1). Fresh top-level list — no typed-map.
-    bundle['activity_curve'] = _activityCurve(daySub);
-
-    // ── AUTO-DETECTED WORKOUTS (WorkoutDetector, 1 Hz HR + gravity) ──────────
-    // Retroactive bout detection over the day's HR + gravity (lives in daySub,
-    // not the bundle input). Per-bout strain/zones/calories via the analytics
-    // family. OVERLAP-DEDUP: any manual/live session for this day is passed as a
-    // saved span so a detected bout overlapping it is dropped (manual wins). The
-    // sport seam stays default ("detected") — OpenStrap's HAR typer can be wired
-    // in once high-rate accel features exist.
-    bundle['detected_workouts'] = await _detectedWorkouts(daySub, day, profile);
-
-    // ── AUTO-WORKOUT SUGGESTIONS + HRR (opt-in detector over day HR+motion) ──
-    // One pass of the opt-in detector serves two features: (1) persisted "did you
-    // work out?" suggestions + a recent-day notification, and (2) heart-rate
-    // recovery (HRR) per bout → `hrr_bpm` scalar. scMap writes through to
-    // bundle['scalars'] (CastMap view), so hrr_bpm reaches the series block below.
-    await _attachWorkoutSuggestionsAndHrr(bundle, scMap, daySub, day, dataNowSec);
-
-    // ── WRIST ORIENTATION during sleep (low-confidence; NOT body position) ───
-    _attachWristOrientation(
-        bundle, daySub, day.sleepOnsetSec, day.sleepOffsetSec);
-
-    // ── ADVANCED SLEEP (4-class Cole–Kripke + DoG/percentile stager) ─────────
-    // A richer, AASM-style sleep read (SOL / REM-latency / disturbances + a
-    // 4-class hypnogram) computed over the day substrate (needs accel, which
-    // lives here, not in the bundle input). ADDITIVE: the canonical single-source
-    // `sleep` block (from segmentSleep) is the headline; this is a parallel
-    // ESTIMATE detail. Best-effort — never throws.
-    bundle['advanced_sleep'] = await _advancedSleep(daySub);
-
-    // Feature 6: Restlessness Map (Heatmap of Sleep)
-    if (sleepSub.length > 0) {
-      final bucketSec = 300; // 5 min
-      final moveSum = <int, double>{};
-      final moveCount = <int, int>{};
-      for (var i = 0; i < sleepSub.length; i++) {
-        final b = sleepSub.tsSec[i] ~/ bucketSec;
-        final ax = sleepSub.ax[i];
-        final ay = sleepSub.ay[i];
-        final az = sleepSub.az[i];
-        final mag = math.sqrt(ax * ax + ay * ay + az * az);
-        final enmo = (mag - 1.0).abs();
-        moveSum[b] = (moveSum[b] ?? 0.0) + enmo;
-        moveCount[b] = (moveCount[b] ?? 0) + 1;
+    // ── SECOND HALF — OFFLOADED to a background isolate ──────────────────────
+    // Everything that turns the isolate-1 bundle into the full day result (wake
+    // features, hybrid steps + TDEE, all-day HRV/RSA/skin-temp Timeline lines,
+    // naps, workout detection + HRR, wrist orientation, restlessness map, fit
+    // quality) used to run on the CALLING isolate — the UI isolate for the
+    // foreground light pass that fires on every sync — hanging the main thread
+    // for seconds (the rolling-RSA Lomb-Scargle over the 24 h day + nap
+    // re-staging + workout detection are the trig/CPU hogs). It is all PURE
+    // compute over the two substrates + a few scalars, so it now runs in
+    // Isolate.run. DB reads that it needs are done HERE (this is the DB-owning
+    // isolate); the DB writes + notification it produces are returned as
+    // descriptors and applied below. Same _perDayTimeout guard as isolate 1.
+    // NON-FATAL: a failure OR timeout anywhere in the offloaded second half must
+    // never skip the whole day. Isolate 1 already computed the headline scalars
+    // (readiness / RHR / RMSSD) into bundle['scalars']; we persist those and just
+    // drop the optional detail blocks. (Previously an exception here threw out of
+    // _derivePreparedDay → the day was marked skipped → readiness rendered "-"
+    // even though it had been computed fine — the "readiness randomly goes -" bug.)
+    // `secondHalfOk` tracks whether this actually completed: a headline-only
+    // row must be marked `partial` below so it never locks as finalized and
+    // never counts as "derived" for the raw-pruning guard (see
+    // LocalDb.dayResultIds) — otherwise a transient failure here permanently
+    // loses the ability to ever back-fill naps/workouts/HRR/wear/curves for
+    // this day once its raw substrate is pruned.
+    var secondHalfOk = true;
+    try {
+      final dayLo = daySub.length == 0 ? 0 : daySub.tsSec.first;
+      final dayHi = daySub.length == 0 ? 0 : daySub.tsSec.last + 60;
+      final coverageWindows =
+          await LocalDb.coverageWindowsOverlapping(dayLo, dayHi);
+      final liveStepsReal = await LocalDb.liveStepsForDay(day.date);
+      final stepCalib = await LocalDb.getStepCalibration();
+      final savedSessions = await LocalDb.sessionsInRange(dayLo, dayHi);
+
+      // Built on THIS isolate so the Isolate.run closure captures only this plain
+      // sendable object (never `this`, `day`, or `bundle`).
+      final blocksInput = _DayBlocksInput(
+        daySub: daySub,
+        sleepSub: sleepSub,
+        profile: profile,
+        onsetSec: day.sleepOnsetSec,
+        offsetSec: day.sleepOffsetSec,
+        rhr: (scMap?['rhr'] as num?)?.toDouble(),
+        maxHrUsed: (bundle['max_hr_used'] as num?)?.round(),
+        coverageWindows: coverageWindows,
+        liveStepsReal: liveStepsReal,
+        stepCalib: stepCalib,
+        savedSessions: savedSessions,
+        date: day.date,
+        dayEndSec: day.endSec,
+        dataNowSec: dataNowSec,
+      );
+      final blocks =
+          await _runDayBlocksCancellable(blocksInput, _perDayTimeout);
+
+      // Merge the computed blocks back into the isolate-1 bundle. scMap is the
+      // CastMap view over bundle['scalars'], so addAll writes through — nap_min /
+      // hrr_bpm reach the persisted series map below.
+      bundle.addAll(blocks.bundlePatch);
+      (bundle['series'] as Map?)?.cast<String, dynamic>().addAll(
+            blocks.seriesPatch,
+          );
+      scMap?.addAll(blocks.scalarPatch);
+
+      // DB writes + notification the pure compute deferred to us (DB-owning isolate).
+      for (final w in blocks.sessionHrrWrites) {
+        await LocalDb.setSessionHrr(w.$1, w.$2);
       }
-      final out = <Map<String, dynamic>>[];
-      final keys = moveSum.keys.toList()..sort();
-      for (final b in keys) {
-        final avgEnmo = moveSum[b]! / moveCount[b]!;
-        // 0.1g ENMO is quite restless. Scale to 0-1 for heatmap UI.
-        final density = math.min(1.0, avgEnmo * 10.0);
-        out.add({
-          't': b * bucketSec,
-          'density': double.parse(density.toStringAsFixed(3)),
+      for (final sug in blocks.suggestionsToPersist) {
+        await LocalDb.putWorkoutSuggestion({
+          ...sug,
+          'created_at': DateTime.now().millisecondsSinceEpoch,
         });
       }
-      bundle['restlessness_map'] = out;
-    }
-
-    // Feature 2: Fit Quality Diagnostics (Band Too Loose)
-    // Analyze skinContact during active periods (HR > 100)
-    var activeContactSum = 0;
-    var activeContactN = 0;
-    for (var i = 0; i < daySub.length; i++) {
-      if (daySub.hr[i] > 100 && daySub.skinContact[i] > 0) {
-        activeContactSum += daySub.skinContact[i];
-        activeContactN++;
-      }
-    }
-    if (activeContactN > 60) { // at least 1 minute of activity
-      final avgContact = activeContactSum / activeContactN;
-      if (avgContact < 100) {
-        bundle['fit_quality'] = 'poor';
-        bundle['fit_warning'] = 'Band is worn too loosely during high activity. Tighten for accurate HR.';
+      final nb = blocks.notifBout;
+      if (nb != null) {
+        await NotificationCenter.instance.emit(
+          NotificationEvent(
+            dedupeKey: '${day.date}:auto_workout',
+            category: NotifCategory.recovery,
+            priority: NotifPriority.normal,
+            title: 'Did you work out?',
+            body: 'We spotted ~${nb.durationMin} min of elevated activity. '
+                'Tap to log it.',
+            date: day.date,
+            route: '/workouts',
+          ),
+          // This runs from headless background derivation too — never prompt
+          // for permission from a background context (violates the OS
+          // background contract and can incorrectly cache permission=denied).
+          allowPermissionPrompt: false,
+        );
       }
-    }
 
-    await _persistWakeDayFeatures(dayId: day.date, wake: wake);
+      await _persistWakeDayFeatures(dayId: day.date, wake: blocks.wake);
+    } catch (e, st) {
+      secondHalfOk = false;
+      _log('day-blocks (offloaded second half) failed for ${day.date} — '
+          'persisting headline day (partial): $e');
+      TelemetryService.instance.recordNonFatal(e, st, reason: 'day_blocks_failed');
+    }
 
     // Finalize once the DATA EDGE has moved >48 h past the day's wake — i.e. we
     // have continuous drained data well beyond it, so no more flash can land for
     // this day. (Anchored on the last record ts, NOT the wall clock.) Imports
-    // force-finalize: there is no stored raw to ever recompute them from.
-    final finalized =
-        forceFinalize || (day.endSec + _finalizationSec) < dataNowSec;
+    // force-finalize: there is no stored raw to ever recompute them from, so
+    // forceFinalize wins even for a partial (headline-only) result — there's
+    // nothing left to retry regardless. Outside of that, never let a partial
+    // result lock in as finalized purely by age, or its missing naps/
+    // workouts/HRR/wear/curves would never get a chance to be filled in by a
+    // later retry.
+    final ageFinalized = (day.endSec + _finalizationSec) < dataNowSec;
+    final finalized = forceFinalize || (ageFinalized && secondHalfOk);
 
     final scalars =
         (bundle['scalars'] as Map?)?.cast<String, dynamic>() ?? const {};
@@ -1560,6 +1574,7 @@ class DerivationEngine {
         ((day.sleepJson['window'] as Map?) ?? const {}).cast<String, dynamic>(),
       ),
       finalized: finalized,
+      partial: !secondHalfOk,
       rhr: sc('rhr'),
       rmssd: sc('rmssd'),
       readiness: sc('readiness'),
@@ -1978,7 +1993,7 @@ class DerivationEngine {
       'skin_temp_z': sc('skin_temp_z'),
       'trimp': sc('trimp'),
       // Headline 0–21 strain, daily steps, nap minutes — feed Sleep/Strain Coach
-      // + VO₂max/WHOOP-Age in the cross-day rollup.
+      // + VO₂max/Fitness Age in the cross-day rollup.
       'strain': sc('strain'),
       'steps': sc('steps'),
       'nap_min': sc('nap_min'),
@@ -2024,7 +2039,7 @@ class DerivationEngine {
     }
   }
 
-  List<double> _perMinuteMeanWake(
+  static List<double> _perMinuteMeanWake(
     Substrate s,
     int sleepOnsetSec,
     int sleepOffsetSec,
@@ -2044,7 +2059,7 @@ class DerivationEngine {
     return [for (final k in keys) _meanWake(buckets[k]!)!];
   }
 
-  Map<String, int> _wakeZoneMinutes(
+  static Map<String, int> _wakeZoneMinutes(
     Substrate s,
     int sleepOnsetSec,
     int sleepOffsetSec,
@@ -2066,7 +2081,7 @@ class DerivationEngine {
     return ana.HeartRateZones.timeInZone(samples, zoneSet).toRoundedMinuteMap();
   }
 
-  double _keytelCaloriesWake(
+  static double _keytelCaloriesWake(
     List<double> perMin,
     double age,
     double weight,
@@ -2084,7 +2099,7 @@ class DerivationEngine {
     return kcal;
   }
 
-  double? _meanWake(List<double> xs) {
+  static double? _meanWake(List<double> xs) {
     if (xs.isEmpty) return null;
     var s = 0.0;
     for (final x in xs) {
@@ -2093,7 +2108,7 @@ class DerivationEngine {
     return s / xs.length;
   }
 
-  void _applyWakeDayFeatures(
+  static void _applyWakeDayFeatures(
     Map<String, dynamic> bundle,
     Map<String, dynamic>? scMap,
     Map<String, dynamic> wake,
@@ -2123,7 +2138,7 @@ class DerivationEngine {
   /// NOT cover ([coverageWindows], device-time sec). So a minute is counted by
   /// 100 Hz OR estimated by 1 Hz, never both. TDEE = HR-flex (Mifflin BMR floor +
   /// active Keytel surplus). Best-effort.
-  void _stepsAndEnergy(
+  static void _stepsAndEnergy(
     Map<String, dynamic> bundle,
     Map<String, dynamic>? scMap,
     Substrate daySub,
@@ -2216,7 +2231,7 @@ class DerivationEngine {
         }
       }
     } catch (e) {
-      _log('steps/energy skipped: $e');
+      if (kDebugMode) debugPrint('[derive] steps/energy skipped: $e');
     }
   }
 
@@ -2232,7 +2247,7 @@ class DerivationEngine {
     );
   }
 
-  Map<String, dynamic> _buildWakeDayFeatures(
+  static Map<String, dynamic> _buildWakeDayFeatures(
     Substrate daySub,
     Profile profile, {
     required int sleepOnsetSec,
@@ -2343,7 +2358,7 @@ class DerivationEngine {
   }
 
   /// Active minutes over the WAKE span — a coarse 1 Hz movement proxy.
-  int _activeMinutes(Substrate s, int sleepOnsetSec, int sleepOffsetSec) {
+  static int _activeMinutes(Substrate s, int sleepOnsetSec, int sleepOffsetSec) {
     final n = s.length;
     if (n < 60) return 0;
     final ang = List<double>.filled(n, 0);
@@ -2374,7 +2389,7 @@ class DerivationEngine {
     return active;
   }
 
-  List<ana.MotionMinute> _motionMinutes(Substrate s) {
+  static List<ana.MotionMinute> _motionMinutes(Substrate s) {
     final samples = <ana.AccelSample>[
       for (var i = 0; i < s.length; i++)
         ana.AccelSample(
@@ -2388,7 +2403,7 @@ class DerivationEngine {
     return ana.enmoSeries(samples).minutes;
   }
 
-  List<double> _hrPerMinuteAligned(List<ana.MotionMinute> motion, Substrate s) {
+  static List<double> _hrPerMinuteAligned(List<ana.MotionMinute> motion, Substrate s) {
     final buckets = <int, List<double>>{};
     for (var i = 0; i < s.hr.length && i < s.tsSec.length; i++) {
       if (s.hr[i] <= 0) continue;
@@ -2401,7 +2416,7 @@ class DerivationEngine {
     ];
   }
 
-  String _workoutSex(String? sex) {
+  static String _workoutSex(String? sex) {
     switch ((sex ?? '').toLowerCase()) {
       case 'm':
       case 'male':
@@ -2414,37 +2429,17 @@ class DerivationEngine {
     }
   }
 
-  /// Auto-detected workouts for the day via [ana.WorkoutDetector] over the
-  /// day's 1 Hz HR + gravity. Returns a list of per-bout maps (each bout's
-  /// avg/peak HR, duration, zone time-%, strain, calories, sport). Manual/live
-  /// sessions overlapping the day are passed as saved spans so an overlapping
-  /// detected bout is dropped (OVERLAP-DEDUP; manual wins). Empty list when no
-  /// bout qualifies. Never throws — best-effort, like the other detail blocks.
-  Future<List<Map<String, dynamic>>> _detectedWorkouts(
-    Substrate s,
-    PreparedDerivationDay day,
-    Profile profile,
-  ) async => const [];
-  // NOTE: sport typing (ana.RuleSportClassifier) lived here, attached to detected
-  // workouts. PR#25 relocated workout detection out of _deriveDay, so the per-bout
-  // classifier was removed; re-home it where the new flow surfaces bouts.
-
-  /// Advanced 4-class sleep over the day substrate via [ana.AdvancedSleepStager]
-  /// (Cole–Kripke sleep/wake spine + DoG HR-variability + percentile-band
-  /// classifier + median/physiology smoothing). Returns the MAIN sleep session's
-  /// AASM metrics (TST/SOL/REM-latency/WASO/disturbances + per-stage minutes) and
-  /// a 4-class hypnogram. ADDITIVE — the canonical `sleep` block stays the
-  /// single source; this is a parallel ESTIMATE. `{present:false}` when no
-  /// qualifying sleep / insufficient data. Never throws (best-effort detail).
-  Future<Map<String, dynamic>> _advancedSleep(Substrate s) async => const {
-    'present': false,
-  };
+  // NOTE: `detected_workouts` (`const []`) and `advanced_sleep`
+  // (`{present:false}`) are currently constant stubs — they are now emitted
+  // directly inside [_computeDayBlocks] (the offloaded second half). When the
+  // real WorkoutDetector / AdvancedSleepStager passes are re-homed, put them
+  // back there so they stay OFF the calling isolate.
 
   /// Per-5-min movement-level curve over the whole day ([{t, v}], v = fraction
   /// of seconds in the bucket with a ≥5° wrist-orientation change, 0..1). The
   /// honest 1 Hz movement signal (same basis as active-minutes) for the "Your
   /// day" Movement view. Sleep is NOT excluded — the curve naturally dips there.
-  List<Map<String, dynamic>> _activityCurve(Substrate s) {
+  static List<Map<String, dynamic>> _activityCurve(Substrate s) {
     final n = s.length;
     if (n < 60) return const [];
     final ang = List<double>.filled(n, 0);
@@ -2482,7 +2477,7 @@ class DerivationEngine {
   /// CAVEAT: this assumes the band does NOT keep logging while off-wrist. If a
   /// future firmware streams off-wrist records, add a skin-temp/motion on-body
   /// gate here (the substrate carries accel + skinTemp).
-  Map<String, dynamic> _wearBlock(Substrate s) {
+  static Map<String, dynamic> _wearBlock(Substrate s) {
     final n = s.length;
     if (n == 0) {
       return {
@@ -2547,7 +2542,7 @@ class DerivationEngine {
   /// Timeline graph. 5-min sliding window, emitted ~each minute. Inline artifact
   /// gate (plausible RR 300–2000 ms) — daytime RR is noisier/motion-confounded,
   /// so this is a context line, not the nocturnal recovery RMSSD.
-  List<Map<String, num>> _dayHrvCurve(Substrate s) {
+  static List<Map<String, num>> _dayHrvCurve(Substrate s) {
     final ts = <double>[], rr = <double>[];
     for (var i = 0; i < s.rrMs.length; i++) {
       final v = s.rrMs[i];
@@ -2596,7 +2591,7 @@ class DerivationEngine {
   /// 24/7 RR. 3-min window emitted ~every 5 min; absent windows (too few/too
   /// noisy beats) are skipped — never fabricated. Daytime RSA is movement-
   /// confounded, so it's a context line.
-  List<Map<String, num>> _dayRespCurve(Substrate s) {
+  static List<Map<String, num>> _dayRespCurve(Substrate s) {
     final ts = <double>[], rr = <double>[];
     for (var i = 0; i < s.rrMs.length; i++) {
       final v = s.rrMs[i];
@@ -2636,7 +2631,7 @@ class DerivationEngine {
   /// All-day RELATIVE skin-temperature trend (epoch {t,v}). Per-5-min mean ADC
   /// expressed as a delta from the day's median — RELATIVE only, no absolute °C
   /// (the band has no calibrated temperature). A slow context line.
-  List<Map<String, num>> _daySkinTempCurve(Substrate s) {
+  static List<Map<String, num>> _daySkinTempCurve(Substrate s) {
     final bins = <int, List<double>>{};
     for (var i = 0; i < s.skinTemp.length && i < s.tsSec.length; i++) {
       final v = s.skinTemp[i];
@@ -2656,7 +2651,7 @@ class DerivationEngine {
     ];
   }
 
-  Map<String, dynamic> _daytimeHrv(Substrate s, int onsetSec, int offsetSec) {
+  static Map<String, dynamic> _daytimeHrv(Substrate s, int onsetSec, int offsetSec) {
     const binSec = 300;
     final bins = <int, List<double>>{};
     double? prev;
@@ -2699,7 +2694,7 @@ class DerivationEngine {
 
   /// Nocturnal restlessness from sleep-window orientation change: minutes with
   /// movement, number of distinct movement bouts, longest still stretch (min).
-  Map<String, dynamic> _restlessness(Substrate s) {
+  static Map<String, dynamic> _restlessness(Substrate s) {
     final n = s.length;
     if (n < 60) {
       return {
@@ -2743,7 +2738,7 @@ class DerivationEngine {
 
   /// Sleep periods: the main sleep + any NAPS (still, on-wrist minute-runs ≥20
   /// min OUTSIDE the main window). Conservative — naps need sustained stillness.
-  Map<String, dynamic> _sleepPeriods(Substrate s, int onsetSec, int offsetSec) {
+  static Map<String, dynamic> _sleepPeriods(Substrate s, int onsetSec, int offsetSec) {
     final periods = <Map<String, dynamic>>[];
     var totalAsleep = 0;
     if (offsetSec > onsetSec) {
@@ -2813,7 +2808,7 @@ class DerivationEngine {
   /// + HR-dip over the WAKE span, the main nocturnal window carved out). Writes a
   /// rich `naps` block (per-nap start/end epoch-sec + duration + confidence) and a
   /// `nap_min` scalar (total nap minutes) used by the Sleep Coach + Timeline.
-  void _attachNaps(
+  static void _attachNaps(
     Map<String, dynamic> bundle,
     Map<String, dynamic>? scMap,
     Substrate s,
@@ -2860,27 +2855,244 @@ class DerivationEngine {
       final napMin = naps.fold<int>(0, (a, nap) => a + (nap.durationSec ~/ 60));
       scMap?['nap_min'] = napMin.toDouble();
     } catch (e) {
-      _log('naps FAILED/skipped: $e');
+      if (kDebugMode) debugPrint('[derive] naps FAILED/skipped: $e');
     }
   }
 
-  /// Opt-in workout SUGGESTIONS (`autoDetectWorkouts`) + HEART-RATE RECOVERY.
+  /// Runs [_computeDayBlocks] in an explicitly spawned, killable isolate and
+  /// enforces [timeout] on the isolate itself — not just on the caller's wait.
   ///
-  /// One detector pass over the day's 1 Hz HR (+ gravity motion) serves both: the
-  /// detected bouts become persisted "did you work out?" suggestions (excluding
-  /// any already-saved manual/live session), and each bout's HR tail yields an
-  /// HRR-60s drop whose daily mean → `hrr_bpm`. Suggestions + the notification are
-  /// gated to RECENT days so a re-analyze / import never spams. Best-effort.
-  Future<void> _attachWorkoutSuggestionsAndHrr(
-    Map<String, dynamic> bundle,
-    Map<String, dynamic>? scMap,
-    Substrate s,
-    PreparedDerivationDay day,
-    int dataNowSec,
+  /// `Isolate.run(...).timeout(...)` (the previous approach) only stops the
+  /// CALLER from awaiting the result; the spawned isolate keeps executing to
+  /// completion in the background regardless. Under a multi-day backlog with
+  /// a bounded worker pool ([_deriveConcurrency]), a slow/hung day's abandoned
+  /// isolate can keep burning CPU well after its caller moved on to the next
+  /// day — silently exceeding the intended concurrency budget. Spawning the
+  /// isolate ourselves gives us a handle to actually `kill()` it on timeout.
+  static Future<_DayBlocksOutput> _runDayBlocksCancellable(
+    _DayBlocksInput input,
+    Duration timeout,
   ) async {
+    final port = ReceivePort();
+    final isolate = await Isolate.spawn(
+      _dayBlocksIsolateEntry,
+      (port.sendPort, input),
+      onError: port.sendPort,
+      onExit: port.sendPort,
+    );
+    final completer = Completer<_DayBlocksOutput>();
+    late final StreamSubscription<dynamic> sub;
+    sub = port.listen((message) {
+      if (completer.isCompleted) return;
+      if (message is _DayBlocksOutput) {
+        completer.complete(message);
+      } else if (message is List) {
+        // Either our own caught-exception report (`[error, stack]`) or the
+        // `onError` port's uncaught-error format — both are 2-element lists
+        // of strings. `onExit` fires with `null`, which we treat as "the
+        // isolate ended without ever sending a result" below.
+        completer.completeError(
+          StateError(
+            message.isNotEmpty
+                ? 'day-blocks isolate failed: ${message.first}'
+                : 'day-blocks isolate failed with no error detail',
+          ),
+        );
+      } else if (message == null) {
+        if (!completer.isCompleted) {
+          completer.completeError(
+            StateError('day-blocks isolate exited without a result'),
+          );
+        }
+      }
+    });
+    try {
+      return await completer.future.timeout(
+        timeout,
+        onTimeout: () {
+          isolate.kill(priority: Isolate.immediate);
+          throw TimeoutException(
+            'day-blocks computation timed out after $timeout',
+          );
+        },
+      );
+    } finally {
+      await sub.cancel();
+      port.close();
+      // No-op if the isolate already exited normally; guarantees a hung or
+      // still-running isolate never outlives this call.
+      isolate.kill(priority: Isolate.immediate);
+    }
+  }
+
+  /// `Isolate.spawn` entry point for [_runDayBlocksCancellable]. Must be a
+  /// static/top-level function taking exactly one (sendable) argument.
+  static void _dayBlocksIsolateEntry((SendPort, _DayBlocksInput) args) {
+    final (sendPort, input) = args;
+    try {
+      sendPort.send(_computeDayBlocks(input));
+    } catch (e, st) {
+      sendPort.send([e.toString(), st.toString()]);
+    }
+  }
+
+  /// The full PURE second half of per-day derivation, run OFF the calling
+  /// isolate via a cancellable spawned isolate (see [_runDayBlocksCancellable],
+  /// [_derivePreparedDay]). Previously ALL of this ran on whatever isolate
+  /// drove the engine — the UI isolate for the foreground light pass fired on
+  /// every sync — producing multi-second main-thread hangs (rolling RSA
+  /// Lomb-Scargle over the 24 h day, nap re-staging, workout detection, wake
+  /// features, steps/energy). DB reads are performed by the caller and passed
+  /// in; DB writes + notifications are returned as descriptors for the caller
+  /// to apply.
+  static _DayBlocksOutput _computeDayBlocks(_DayBlocksInput inp) {
+    final daySub = inp.daySub;
+    final sleepSub = inp.sleepSub;
+    final onset = inp.onsetSec;
+    final offset = inp.offsetSec;
+    final bundlePatch = <String, dynamic>{};
+    final seriesPatch = <String, dynamic>{};
+    // Working scalars — seeded with the nightly RHR the pure helpers read
+    // (steps/energy + wake features gate on it). The seed is removed from the
+    // returned patch so we only write back the NEWLY computed scalars.
+    final scMap = <String, dynamic>{'rhr': inp.rhr};
+
+    // Wake-day features (active min / strain / calories / steps / zones / wear),
+    // then the hybrid 100 Hz + 1 Hz steps + TDEE override (order preserved).
+    final wake = _buildWakeDayFeatures(
+      daySub,
+      inp.profile,
+      sleepOnsetSec: onset,
+      sleepOffsetSec: offset,
+      restingHr: inp.rhr,
+    );
+    _applyWakeDayFeatures(bundlePatch, scMap, wake);
+    _stepsAndEnergy(
+      bundlePatch,
+      scMap,
+      daySub,
+      inp.profile,
+      inp.coverageWindows,
+      inp.liveStepsReal,
+      inp.stepCalib,
+    );
+    // _stepsAndEnergy just corrected `steps`/`calories_total` in bundlePatch +
+    // scMap using the hybrid real-100Hz + 1Hz-estimate count, but `wake` (built
+    // above by _buildWakeDayFeatures, before this correction ran) still holds
+    // the earlier 1Hz-only estimate. `wake` is what _persistWakeDayFeatures
+    // stores and what the Today repository reads while the full day result
+    // isn't ready yet, so copy the corrected values back in to avoid serving
+    // stale steps/calories from that early-read path.
+    for (final key in const ['steps', 'calories_total']) {
+      final value = scMap[key];
+      if (value != null) wake[key] = value;
+    }
+
+    bundlePatch['daytime_hrv'] = _daytimeHrv(daySub, onset, offset);
+    seriesPatch['hrv_day'] = _dayHrvCurve(daySub);
+    seriesPatch['resp_day'] = _dayRespCurve(daySub);
+    seriesPatch['skin_temp_day'] = _daySkinTempCurve(daySub);
+    bundlePatch['restlessness'] = _restlessness(sleepSub);
+    bundlePatch['sleep_periods'] = _sleepPeriods(daySub, onset, offset);
+    _attachNaps(bundlePatch, scMap, daySub, onset, offset);
+    // Overrides wake's activity_curve (same value, computed once here).
+    bundlePatch['activity_curve'] = _activityCurve(daySub);
+    bundlePatch['detected_workouts'] = const <Map<String, dynamic>>[];
+
+    final wc = _computeWorkouts(
+      s: daySub,
+      maxHr: inp.maxHrUsed,
+      rhrScalar: inp.rhr,
+      saved: inp.savedSessions,
+      date: inp.date,
+      dayEndSec: inp.dayEndSec,
+      dataNowSec: inp.dataNowSec,
+    );
+    bundlePatch['workout_suggestions'] = wc.boutJson;
+    if (wc.hrrBpm != null) scMap['hrr_bpm'] = wc.hrrBpm;
+
+    _attachWristOrientation(bundlePatch, daySub, onset, offset);
+    bundlePatch['advanced_sleep'] = const {'present': false};
+
+    // Feature 6: Restlessness Map (5-min ENMO heatmap of the sleep window).
+    if (sleepSub.length > 0) {
+      const bucketSec = 300; // 5 min
+      final moveSum = <int, double>{};
+      final moveCount = <int, int>{};
+      for (var i = 0; i < sleepSub.length; i++) {
+        final b = sleepSub.tsSec[i] ~/ bucketSec;
+        final ax = sleepSub.ax[i];
+        final ay = sleepSub.ay[i];
+        final az = sleepSub.az[i];
+        final mag = math.sqrt(ax * ax + ay * ay + az * az);
+        final enmo = (mag - 1.0).abs();
+        moveSum[b] = (moveSum[b] ?? 0.0) + enmo;
+        moveCount[b] = (moveCount[b] ?? 0) + 1;
+      }
+      final out = <Map<String, dynamic>>[];
+      final keys = moveSum.keys.toList()..sort();
+      for (final b in keys) {
+        final avgEnmo = moveSum[b]! / moveCount[b]!;
+        final density = math.min(1.0, avgEnmo * 10.0);
+        out.add({
+          't': b * bucketSec,
+          'density': double.parse(density.toStringAsFixed(3)),
+        });
+      }
+      bundlePatch['restlessness_map'] = out;
+    }
+
+    // Feature 2: Fit-quality diagnostic (band too loose during high activity).
+    var activeContactSum = 0;
+    var activeContactN = 0;
+    for (var i = 0; i < daySub.length; i++) {
+      if (daySub.hr[i] > 100 && daySub.skinContact[i] > 0) {
+        activeContactSum += daySub.skinContact[i];
+        activeContactN++;
+      }
+    }
+    if (activeContactN > 60) {
+      final avgContact = activeContactSum / activeContactN;
+      if (avgContact < 100) {
+        bundlePatch['fit_quality'] = 'poor';
+        bundlePatch['fit_warning'] =
+            'Band is worn too loosely during high activity. Tighten for accurate HR.';
+      }
+    }
+
+    scMap.remove('rhr'); // seed only; the real rhr scalar already lives in the bundle
+    return _DayBlocksOutput(
+      bundlePatch: bundlePatch,
+      seriesPatch: seriesPatch,
+      scalarPatch: scMap,
+      wake: wake,
+      suggestionsToPersist: wc.suggestionsToPersist,
+      sessionHrrWrites: wc.sessionHrrWrites,
+      notifBout: wc.notifBout,
+    );
+  }
+
+  /// PURE compute half of workout SUGGESTIONS (`autoDetectWorkouts`) + HRR.
+  ///
+  /// Runs inside the day-blocks isolate: one detector pass over the day's 1 Hz HR
+  /// (+ gravity motion) yields the detected bouts (excluding any already-saved
+  /// manual/live session, passed in via [saved] which the caller read from the DB
+  /// on the DB-owning isolate) and each bout's HR-tail HRR-60s drop. Returns the
+  /// bout JSON, the mean `hrr_bpm`, the retrospective per-session HRR writes, the
+  /// recent-day suggestions to persist, and the freshly-ended notif candidate —
+  /// the DB writes + notification are performed by the caller on the main isolate.
+  static _WorkoutCompute _computeWorkouts({
+    required Substrate s,
+    required int? maxHr,
+    required double? rhrScalar,
+    required List<Map<String, dynamic>> saved,
+    required String date,
+    required int dayEndSec,
+    required int dataNowSec,
+  }) {
     try {
       final n = s.length;
-      if (n < 60) return;
+      if (n < 60) return const _WorkoutCompute.empty();
       final hrTs = <int>[];
       final hrBpm = <int>[];
       for (var i = 0; i < n; i++) {
@@ -2889,22 +3101,16 @@ class DerivationEngine {
           hrBpm.add(s.hr[i]);
         }
       }
-      if (hrBpm.length < 60) return;
+      if (hrBpm.length < 60) return const _WorkoutCompute.empty();
       final motion =
           ana.AutoWorkoutDetector.motionPoints(s.tsSec, s.ax, s.ay, s.az);
       // Exclude windows the user has already logged (manual/live wins).
-      final dayLo = s.tsSec.first;
-      final dayHi = s.tsSec.last + 60;
-      final saved = await LocalDb.sessionsInRange(dayLo, dayHi);
       final savedSpans = <ana.SavedWorkoutSpan>[
         for (final r in saved)
           if (r['start_ts'] is int && r['end_ts'] is int)
             ana.SavedWorkoutSpan(r['start_ts'] as int, r['end_ts'] as int),
       ];
-      final rhr = (scMap?['rhr'] as num?)?.round();
-      // Age-predicted HRmax (Tanaka) computed by the pipeline — drives the %HRR
-      // gate in the detector. Null when age is unknown (detector falls back).
-      final maxHr = (bundle['max_hr_used'] as num?)?.round();
+      final rhr = rhrScalar?.round();
       // Auto-detection needs a real resting-HR baseline. Without one the detector
       // can't compute a trustworthy %HRR floor and ordinary daytime HR reads as a
       // workout. If we don't have a nightly RHR for this day yet, skip detection
@@ -2940,6 +3146,7 @@ class DerivationEngine {
       // Also fill HRR for already-saved sessions (manual/live) retrospectively
       // from the substrate around each session's end — so the workout detail
       // screen shows HRR without buffering 60 s after a live stop.
+      final sessionHrr = <(String, double)>[];
       for (final r in saved) {
         final id = r['id'];
         final endTs = r['end_ts'];
@@ -2947,23 +3154,24 @@ class DerivationEngine {
         final m = _hrrForBout(s, endTs);
         if (m != null) {
           drops.add(m);
-          await LocalDb.setSessionHrr(id, double.parse(m.toStringAsFixed(1)));
+          sessionHrr.add((id, double.parse(m.toStringAsFixed(1))));
         }
       }
-      if (drops.isNotEmpty) {
-        final mean = drops.reduce((a, c) => a + c) / drops.length;
-        scMap?['hrr_bpm'] = double.parse(mean.toStringAsFixed(1));
-      }
-      bundle['workout_suggestions'] = boutJson;
+      final hrrBpm = drops.isEmpty
+          ? null
+          : double.parse(
+              (drops.reduce((a, c) => a + c) / drops.length).toStringAsFixed(1));
 
       // Persist + notify only for RECENT days (≤ ~36 h old) so imports/re-analyze
       // don't resurface 90 days of prompts.
-      final recent = (dataNowSec - day.endSec) < 36 * 3600;
+      final recent = (dataNowSec - dayEndSec) < 36 * 3600;
+      final toPersist = <Map<String, dynamic>>[];
+      ({int endSec, int durationMin})? notif;
       if (recent && bouts.isNotEmpty) {
         for (final b in bouts) {
-          await LocalDb.putWorkoutSuggestion({
-            'id': '${day.date}:${b.startSec}',
-            'date': day.date,
+          toPersist.add({
+            'id': '$date:${b.startSec}',
+            'date': date,
             'start_ts': b.startSec,
             'end_ts': b.endSec,
             'avg_bpm': b.avgBpm,
@@ -2971,7 +3179,6 @@ class DerivationEngine {
             'duration_min': b.durationMin,
             'sport': b.sport,
             'dismissed': 0,
-            'created_at': DateTime.now().millisecondsSinceEpoch,
           });
         }
         // Notify ONLY for a bout that ended in the last ~2 h (a near-real-time
@@ -2979,30 +3186,27 @@ class DerivationEngine {
         // day at once; without this every hours-old bout would fire a "did you work
         // out?" prompt → a wall of notifications. Suggestions are still persisted
         // above so they surface in the Workouts screen; we just don't ping for them.
-        final newest =
-            bouts.reduce((a, b) => a.endSec >= b.endSec ? a : b);
-        final freshlyEnded = (dataNowSec - newest.endSec) < 2 * 3600;
-        if (freshlyEnded) {
-          await NotificationCenter.instance.emit(NotificationEvent(
-            dedupeKey: '${day.date}:auto_workout',
-            category: NotifCategory.recovery,
-            priority: NotifPriority.normal,
-            title: 'Did you work out?',
-            body: 'We spotted ~${newest.durationMin} min of elevated activity. '
-                'Tap to log it.',
-            date: day.date,
-            route: '/workouts',
-          ));
+        final newest = bouts.reduce((a, b) => a.endSec >= b.endSec ? a : b);
+        if ((dataNowSec - newest.endSec) < 2 * 3600) {
+          notif = (endSec: newest.endSec, durationMin: newest.durationMin);
         }
       }
+      return _WorkoutCompute(
+        boutJson: boutJson,
+        hrrBpm: hrrBpm,
+        sessionHrrWrites: sessionHrr,
+        suggestionsToPersist: toPersist,
+        notifBout: notif,
+      );
     } catch (e) {
-      _log('auto-workout/HRR FAILED/skipped: $e');
+      if (kDebugMode) debugPrint('[derive] auto-workout/HRR FAILED/skipped: $e');
+      return const _WorkoutCompute.empty();
     }
   }
 
   /// HRR-60s for a bout ending at [endSec]: build the per-second HR tail around
   /// the end index and delegate to [ana.hrRecovery]. Returns the drop (bpm) or null.
-  double? _hrrForBout(Substrate s, int endSec) {
+  static double? _hrrForBout(Substrate s, int endSec) {
     final n = s.length;
     if (n == 0) return null;
     // Find the index nearest the bout end.
@@ -3026,7 +3230,7 @@ class DerivationEngine {
   /// Explicitly a WRIST measure (body-position PROXY), never claimed as the
   /// sleeper's supine/side/prone body position. Emits a dominant-orientation
   /// summary + per-position minutes + an orientation-change count. Best-effort.
-  void _attachWristOrientation(
+  static void _attachWristOrientation(
     Map<String, dynamic> bundle,
     Substrate s,
     int onsetSec,
@@ -3071,7 +3275,7 @@ class DerivationEngine {
             'independently of the torso.',
       };
     } catch (e) {
-      _log('wrist-orientation FAILED/skipped: $e');
+      if (kDebugMode) debugPrint('[derive] wrist-orientation FAILED/skipped: $e');
     }
   }
 
@@ -3116,6 +3320,88 @@ class DerivationEngine {
   }
 }
 
+/// Sendable input for [DerivationEngine._computeDayBlocks] — crosses the
+/// `Isolate.run` boundary, so every field is plain data (Substrate is int/double
+/// lists; Profile/StepCalibration are primitive data classes). DB reads that the
+/// pure compute needs are performed by the caller and passed in here.
+class _DayBlocksInput {
+  final Substrate daySub;
+  final Substrate sleepSub;
+  final Profile profile;
+  final int onsetSec;
+  final int offsetSec;
+  final double? rhr;
+  final int? maxHrUsed;
+  final List<List<int>> coverageWindows;
+  final int liveStepsReal;
+  final ana.StepCalibration? stepCalib;
+  final List<Map<String, dynamic>> savedSessions;
+  final String date;
+  final int dayEndSec;
+  final int dataNowSec;
+  const _DayBlocksInput({
+    required this.daySub,
+    required this.sleepSub,
+    required this.profile,
+    required this.onsetSec,
+    required this.offsetSec,
+    required this.rhr,
+    required this.maxHrUsed,
+    required this.coverageWindows,
+    required this.liveStepsReal,
+    required this.stepCalib,
+    required this.savedSessions,
+    required this.date,
+    required this.dayEndSec,
+    required this.dataNowSec,
+  });
+}
+
+/// Sendable output of [DerivationEngine._computeDayBlocks]. [bundlePatch] /
+/// [seriesPatch] / [scalarPatch] are merged into the isolate-1 bundle on the main
+/// isolate; [wake] is persisted; [suggestionsToPersist] / [sessionHrrWrites] /
+/// [notifBout] are the DB writes + notification the caller applies.
+class _DayBlocksOutput {
+  final Map<String, dynamic> bundlePatch;
+  final Map<String, dynamic> seriesPatch;
+  final Map<String, dynamic> scalarPatch;
+  final Map<String, dynamic> wake;
+  final List<Map<String, dynamic>> suggestionsToPersist;
+  final List<(String, double)> sessionHrrWrites;
+  final ({int endSec, int durationMin})? notifBout;
+  const _DayBlocksOutput({
+    required this.bundlePatch,
+    required this.seriesPatch,
+    required this.scalarPatch,
+    required this.wake,
+    required this.suggestionsToPersist,
+    required this.sessionHrrWrites,
+    required this.notifBout,
+  });
+}
+
+/// Result of the pure workout compute ([DerivationEngine._computeWorkouts]).
+class _WorkoutCompute {
+  final List<Map<String, dynamic>> boutJson;
+  final double? hrrBpm;
+  final List<(String, double)> sessionHrrWrites;
+  final List<Map<String, dynamic>> suggestionsToPersist;
+  final ({int endSec, int durationMin})? notifBout;
+  const _WorkoutCompute({
+    required this.boutJson,
+    required this.hrrBpm,
+    required this.sessionHrrWrites,
+    required this.suggestionsToPersist,
+    required this.notifBout,
+  });
+  const _WorkoutCompute.empty()
+      : boutJson = const [],
+        hrrBpm = null,
+        sessionHrrWrites = const [],
+        suggestionsToPersist = const [],
+        notifBout = null;
+}
+
 double? _median(List<double> xs) {
   if (xs.isEmpty) return null;
   final vs = List<double>.from(xs)..sort();
diff --git a/lib/data/db.dart b/lib/data/db.dart
index 89bcf719..aa9bf979 100644
--- a/lib/data/db.dart
+++ b/lib/data/db.dart
@@ -25,8 +25,15 @@ class LocalDb {
   static String dbName = 'openstrap.db';
 
   static Future<Database> get instance async {
-    _db ??= await _open();
-    return _db!;
+    final db = _db;
+    // `_db != null` is NOT enough: Android can close the underlying
+    // SQLiteDatabase on background teardown without our close() ever nulling
+    // `_db`. A plain `_db ??=` then keeps handing back that dead handle, and
+    // every write throws `DatabaseException(attempt to re-open an already-closed
+    // object)` — a sustained crash burst (seen in the wild on background event
+    // ingest). Reopen whenever the cached handle isn't actually open.
+    if (db != null && db.isOpen) return db;
+    return _db = await _open();
   }
 
   static Future<void> close() async {
@@ -280,11 +287,27 @@ class LocalDb {
           // this is right.
           await _ensureDayResultSkippedColumn(db);
         }
+        if (oldV < 25) {
+          // Same class of bug as `skipped` above, different failure mode: the
+          // offloaded second-half day-blocks compute (naps/workouts/HRR/wear/
+          // curves/wake-features) can throw or time out AFTER the first-half
+          // headline scalars (readiness/RHR/RMSSD) already succeeded. That
+          // path is non-fatal by design (the day still gets a real,
+          // non-skipped day_result row so headline scalars display), but the
+          // raw-pruning guard only excluded `skipped` rows - a headline-only
+          // partial row still counted as "derived" and let the raw substrate
+          // it would need to fill in those missing blocks get pruned for
+          // good. This column lets the guard exclude partial rows too.
+          // Existing rows default to 0 (not partial) - can't know in
+          // hindsight which old rows were partial, but going forward this is
+          // right.
+          await _ensureDayResultPartialColumn(db);
+        }
       },
       onOpen: (db) async {
         await _repairOpenSchema(db);
       },
-      version: 24,
+      version: 25,
     );
   }
 
@@ -332,6 +355,7 @@ class LocalDb {
     await _createWorkoutRoute(db);
     await _ensureWorkoutRouteSpeed(db);
     await _ensureDayResultSkippedColumn(db);
+    await _ensureDayResultPartialColumn(db);
     // Views LAST — they depend on metric_series / day_result / baselines / sessions
     // / notifications all existing. DROP+CREATE so a shape change takes effect.
     await _ensureCoachViews(db);
@@ -352,6 +376,20 @@ class LocalDb {
     }
   }
 
+  static Future<void> _ensureDayResultPartialColumn(Database db) async {
+    final info = await db.rawQuery('PRAGMA table_info(day_result)');
+    final has = info.any((c) => c['name'] == 'partial');
+    if (!has) {
+      try {
+        await db.execute(
+          'ALTER TABLE day_result ADD COLUMN partial INTEGER NOT NULL DEFAULT 0',
+        );
+      } catch (_) {
+        /* another opener won the race — column now exists */
+      }
+    }
+  }
+
   // ── MENSTRUAL SYMPTOM LOG ──────────────────────────────────────────────────
   static Future<void> _createCycleSymptom(Database db) async {
     await db.execute('''
@@ -739,6 +777,7 @@ class LocalDb {
         rmssd REAL,
         readiness REAL,
         skipped INTEGER NOT NULL DEFAULT 0,
+        partial INTEGER NOT NULL DEFAULT 0,
         PRIMARY KEY (day_id, algo_version)
       )
     ''');
@@ -2147,6 +2186,15 @@ class LocalDb {
     required String windowJson,
     bool finalized = false,
     bool skipped = false,
+    // A day whose offloaded second-half compute (naps/workouts/HRR/wear/
+    // curves/wake-features) failed or timed out AFTER the headline scalars
+    // already succeeded — the row is real (not a skip marker) so headline
+    // scalars still display, but it must never count as "derived" for the
+    // raw-pruning guard (see dayResultIds). Callers should also avoid passing
+    // `finalized: true` alongside `partial: true` unless there genuinely is
+    // no raw substrate to ever retry from (e.g. the force-finalized import
+    // path), since a finalized row is never revisited on a version bump.
+    bool partial = false,
     double? rhr,
     double? rmssd,
     double? readiness,
@@ -2163,6 +2211,7 @@ class LocalDb {
         'computed_at': now,
         'finalized': finalized ? 1 : 0,
         'skipped': skipped ? 1 : 0,
+        'partial': partial ? 1 : 0,
         'rhr': rhr,
         'rmssd': rmssd,
         'readiness': readiness,
@@ -2211,17 +2260,19 @@ class LocalDb {
     return [for (final r in rows) _withDate(r)];
   }
 
-  /// The set of day_id labels that already have a REAL (non-skipped) result
-  /// at [algoVersion]. Used by the raw-pruning guard to decide what's safe
-  /// to prune - a day that only ever got a skip-marker (its derivation
-  /// threw) must NOT count as "derived" here, or its raw substrate gets
-  /// pruned with no way left to ever compute it correctly.
+  /// The set of day_id labels that already have a REAL, COMPLETE result at
+  /// [algoVersion]. Used by the raw-pruning guard to decide what's safe to
+  /// prune - a day that only ever got a skip-marker (its derivation threw)
+  /// or a partial row (headline scalars only; the offloaded second-half
+  /// blocks failed/timed out) must NOT count as "derived" here, or its raw
+  /// substrate gets pruned with no way left to ever fill in the missing
+  /// data correctly.
   static Future<Set<String>> dayResultIds(int algoVersion) async {
     final db = await instance;
     final rows = await db.query(
       'day_result',
       columns: ['day_id'],
-      where: 'algo_version = ? AND skipped = 0',
+      where: 'algo_version = ? AND skipped = 0 AND partial = 0',
       whereArgs: [algoVersion],
     );
     return {for (final r in rows) r['day_id'] as String};
diff --git a/lib/data/local_repository_impl.dart b/lib/data/local_repository_impl.dart
index d0af2450..3ebda36b 100644
--- a/lib/data/local_repository_impl.dart
+++ b/lib/data/local_repository_impl.dart
@@ -14,6 +14,7 @@
 // Profile-gated metrics are null when the profile field is missing.
 
 import 'dart:convert';
+import 'dart:isolate';
 import 'dart:math' as math;
 
 import '../compute/derivation_engine.dart';
@@ -2299,38 +2300,10 @@ class LocalRepositoryImpl extends LocalRepository {
 
   @override
   Future<Map<String, dynamic>> spotCheck(List<String> records) async {
-    // Decode RR from the live RR-bearing frames (0x28 / R10), clean, compute HRV.
-    final rrMs = <double>[];
-    final hrs = <double>[];
-    for (final hex in records) {
-      final rr = proto.realtimeRr(hex);
-      if (rr != null) {
-        for (final v in rr.rrMs) {
-          if (v > 0) rrMs.add(v.toDouble());
-        }
-      }
-      try {
-        final s = proto.decodeRecord(hex);
-        if (s != null && s.hr > 0) hrs.add(s.hr.toDouble());
-      } catch (_) {}
-    }
-    if (rrMs.length < 20) {
-      return {'ok': false, 'n_beats': rrMs.length};
-    }
-    final cleaned = ana.correctRr(rrMs);
-    final hrv = ana.hrvTime(cleaned.nn, nnTimesMs: cleaned.nnTimesMs);
-    if (!hrv.present) return {'ok': false, 'n_beats': cleaned.nn.length};
-    final meanHr = hrs.isEmpty
-        ? null
-        : hrs.reduce((a, b) => a + b) / hrs.length;
-    return {
-      'ok': true,
-      'rmssd': hrv.value!.rmssd?.round(),
-      'sdnn': hrv.value!.sdnn?.round(),
-      'mean_hr': meanHr?.round(),
-      'n_beats': cleaned.nn.length,
-      'confidence': hrv.confidence,
-    };
+    // Decode + HRV run OFF the UI isolate. The spot-check buffer grows over the
+    // multi-minute measurement, so decoding every frame + RR correction + HRV on
+    // the main isolate was real per-tick work that hung the UI on slower phones.
+    return Isolate.run(() => _spotCheckCompute(records));
   }
 
   @override
@@ -2338,39 +2311,10 @@ class LocalRepositoryImpl extends LocalRepository {
     List<String> records, {
     double? pacedHz,
   }) async {
-    // Decode RR from the live RR-bearing frames (0x28 / R10) — same seam
-    // spotCheck uses — then run McCraty & Zayas 2014 cardiac coherence.
-    final rrMs = <double>[];
-    for (final hex in records) {
-      final rr = proto.realtimeRr(hex);
-      if (rr != null) {
-        for (final v in rr.rrMs) {
-          if (v > 0) rrMs.add(v.toDouble());
-        }
-      }
-    }
-    if (rrMs.length < 20) {
-      return {'ok': false, 'n_beats': rrMs.length};
-    }
-    final cleaned = ana.correctRr(rrMs);
-    final m = ana.cardiacCoherence(cleaned.nn, cleaned.nnTimesMs, pacedHz: pacedHz);
-    if (!m.present) {
-      return {
-        'ok': false,
-        'n_beats': cleaned.nn.length,
-        'note': m.note,
-      };
-    }
-    return {
-      'ok': true,
-      'ratio': m.value!.ratio,
-      'score': m.value!.score.round(),
-      'peak_hz': m.value!.peakHz,
-      'n_beats': cleaned.nn.length,
-      'confidence': m.confidence,
-      'tier': m.tier,
-      'note': m.note,
-    };
+    // Offloaded: cardiac coherence is a 400-point Lomb-Scargle PSD recomputed
+    // over the FULL (growing) session buffer every 20 s — pure sin/cos work that
+    // was running on the UI isolate and is a confirmed foreground-hang source.
+    return Isolate.run(() => _breathingCoherenceCompute(records, pacedHz));
   }
 
   // ── small series helpers ─────────────────────────────────────────────────────
@@ -2421,3 +2365,75 @@ Map<String, dynamic>? stressSummaryForToday(
     'level': score < 34 ? 'low' : (score < 67 ? 'moderate' : 'high'),
   };
 }
+
+// ── Live spot-check / breathing compute (run under Isolate.run, off the UI) ────
+// Top-level (no `this` capture) + only file-scoped `proto`/`ana` top-level
+// functions + a List<String> of hex frames in, a plain Map out — all sendable.
+
+Map<String, dynamic> _spotCheckCompute(List<String> records) {
+  // Decode RR from the live RR-bearing frames (0x28 / R10), clean, compute HRV.
+  final rrMs = <double>[];
+  final hrs = <double>[];
+  for (final hex in records) {
+    final rr = proto.realtimeRr(hex);
+    if (rr != null) {
+      for (final v in rr.rrMs) {
+        if (v > 0) rrMs.add(v.toDouble());
+      }
+    }
+    try {
+      final s = proto.decodeRecord(hex);
+      if (s != null && s.hr > 0) hrs.add(s.hr.toDouble());
+    } catch (_) {}
+  }
+  if (rrMs.length < 20) {
+    return {'ok': false, 'n_beats': rrMs.length};
+  }
+  final cleaned = ana.correctRr(rrMs);
+  final hrv = ana.hrvTime(cleaned.nn, nnTimesMs: cleaned.nnTimesMs);
+  if (!hrv.present) return {'ok': false, 'n_beats': cleaned.nn.length};
+  final meanHr = hrs.isEmpty ? null : hrs.reduce((a, b) => a + b) / hrs.length;
+  return {
+    'ok': true,
+    'rmssd': hrv.value!.rmssd?.round(),
+    'sdnn': hrv.value!.sdnn?.round(),
+    'mean_hr': meanHr?.round(),
+    'n_beats': cleaned.nn.length,
+    'confidence': hrv.confidence,
+  };
+}
+
+Map<String, dynamic> _breathingCoherenceCompute(
+  List<String> records,
+  double? pacedHz,
+) {
+  // Decode RR from the live RR-bearing frames (0x28 / R10) — same seam
+  // spotCheck uses — then run McCraty & Zayas 2014 cardiac coherence.
+  final rrMs = <double>[];
+  for (final hex in records) {
+    final rr = proto.realtimeRr(hex);
+    if (rr != null) {
+      for (final v in rr.rrMs) {
+        if (v > 0) rrMs.add(v.toDouble());
+      }
+    }
+  }
+  if (rrMs.length < 20) {
+    return {'ok': false, 'n_beats': rrMs.length};
+  }
+  final cleaned = ana.correctRr(rrMs);
+  final m = ana.cardiacCoherence(cleaned.nn, cleaned.nnTimesMs, pacedHz: pacedHz);
+  if (!m.present) {
+    return {'ok': false, 'n_beats': cleaned.nn.length, 'note': m.note};
+  }
+  return {
+    'ok': true,
+    'ratio': m.value!.ratio,
+    'score': m.value!.score.round(),
+    'peak_hz': m.value!.peakHz,
+    'n_beats': cleaned.nn.length,
+    'confidence': m.confidence,
+    'tier': m.tier,
+    'note': m.note,
+  };
+}
diff --git a/lib/state/app_state.dart b/lib/state/app_state.dart
index 4746fac7..50eddd5f 100644
--- a/lib/state/app_state.dart
+++ b/lib/state/app_state.dart
@@ -517,14 +517,23 @@ class AppState extends ChangeNotifier {
   UpdateInfo? get _update => appStatus?.update;
 
   /// A newer build is published (we're behind latest_build).
+  ///
+  /// Gated on [UpdateService.supported] (Android + [kSideloadOtaEnabled]):
+  /// store builds (Play Store / App Store) and any non-Android build must
+  /// never surface a self-update prompt at all, not just fall back to a
+  /// browser link — see update_service.dart.
   bool get updateAvailable =>
+      UpdateService.supported &&
       _update != null &&
       _currentBuild > 0 &&
       _update!.latestBuild > _currentBuild;
 
   /// We're below the mandatory floor — the prompt can't be dismissed.
   bool get updateMandatory =>
-      _update != null && _currentBuild > 0 && _currentBuild < _update!.minBuild;
+      UpdateService.supported &&
+      _update != null &&
+      _currentBuild > 0 &&
+      _currentBuild < _update!.minBuild;
 
   UpdateInfo? get update => _update;
 
diff --git a/lib/sync/update_service.dart b/lib/sync/update_service.dart
index c9ff0e9c..60a063ea 100644
--- a/lib/sync/update_service.dart
+++ b/lib/sync/update_service.dart
@@ -1,10 +1,15 @@
-// UpdateService — the Android OTA mechanics. There's no app store in the loop
-// (the app is sideloaded), so we ARE the update channel: download the signed APK
-// from the backend's update pointer and hand it to the system installer. The new
-// APK must be signed with the same release key or Android refuses the update —
-// which is already true for our CI-built GitHub releases.
+// UpdateService — the Android OTA mechanics. On a direct-distribution/sideload
+// build there's no app store in the loop, so we ARE the update channel:
+// download the signed APK from the backend's update pointer and hand it to the
+// system installer. The new APK must be signed with the same release key or
+// Android refuses the update — which is already true for our CI-built GitHub
+// releases.
 //
-// iOS can't sideload-install, so [supported] is false there and the UI hides OTA.
+// iOS can't sideload-install, so [supported] is false there and the UI hides
+// in-app install (falls back to a browser link) regardless of the flag below.
+//
+// Store builds (Play Store, and any future App Store build) must NOT offer
+// self-update at all — see [kSideloadOtaEnabled].
 
 import 'dart:convert';
 import 'dart:io';
@@ -16,6 +21,21 @@ import 'package:url_launcher/url_launcher.dart';
 import '../cloud/companion_client.dart';
 import '../models/app_status.dart';
 
+/// Compile-time gate for the whole self-update feature (the "Update
+/// available" banner AND the in-app APK download/install flow). Defaults OFF
+/// so the open-source repo — and any store submission built from it without
+/// extra flags — never bakes in self-update: app-store review does not allow
+/// an app to silently install another build of itself outside the store.
+///
+/// A direct-distribution/sideload build opts in explicitly:
+///   flutter build apk --dart-define=ENABLE_SIDELOAD_OTA=true
+///
+/// Mirrors the build-time-URL convention in lib/cloud/backend_client.dart /
+/// lib/cloud/companion_client.dart — the public repo must not bake a specific
+/// distribution channel in by default.
+const bool kSideloadOtaEnabled =
+    bool.fromEnvironment('ENABLE_SIDELOAD_OTA', defaultValue: false);
+
 /// A coarse progress event the UI renders.
 class OtaProgress {
   final String phase; // 'downloading' | 'installing' | 'error'
@@ -25,8 +45,9 @@ class OtaProgress {
 }
 
 class UpdateService {
-  /// Only Android can install an APK in-app.
-  static bool get supported => Platform.isAndroid;
+  /// Only Android can install an APK in-app, and only on a sideload build
+  /// that opted into [kSideloadOtaEnabled].
+  static bool get supported => Platform.isAndroid && kSideloadOtaEnabled;
 
   /// Fetch the OTA update pointer + admin alert banner from the companion
   /// backend's public, UNAUTHENTICATED `GET /app/status` — the single URL the app
diff --git a/lib/telemetry/health_uploader.dart b/lib/telemetry/health_uploader.dart
index dd28972f..89aca362 100644
--- a/lib/telemetry/health_uploader.dart
+++ b/lib/telemetry/health_uploader.dart
@@ -16,6 +16,30 @@ import 'package:shared_preferences/shared_preferences.dart';
 import '../cloud/companion_client.dart';
 import '../data/db.dart';
 
+/// Compile-time gate for the whole health-data-contribution feature (this
+/// upload path + the "Contribute my health data" toggle in Settings and
+/// onboarding). Defaults OFF, same convention as [kSideloadOtaEnabled] in
+/// update_service.dart.
+///
+/// NOT enabled by ANY build we distribute — not the GitHub Releases sideload
+/// APK/IPA, and not any future App Store/Play Store submission (CI passes
+/// `ENABLE_HEALTH_DATA_CONTRIBUTION=false` explicitly for both; see
+/// .github/workflows/build.yml). Uploading someone's entire raw + derived
+/// health history to a backend is by far the biggest privacy/compliance
+/// surface this app could have, so PRIVACY.md's "we do not collect your
+/// data" claim is scoped to — and must remain true of — every build we
+/// ourselves ship.
+///
+/// This flag exists purely because the code is open source: an independent
+/// developer compiling their OWN build from this repo can opt in and point
+/// it at a backend of their own choosing. That is their build and their
+/// responsibility, not something our privacy policy governs.
+///   flutter build apk --dart-define=ENABLE_HEALTH_DATA_CONTRIBUTION=true
+const bool kHealthDataContributionEnabled = bool.fromEnvironment(
+  'ENABLE_HEALTH_DATA_CONTRIBUTION',
+  defaultValue: false,
+);
+
 class HealthUploader {
   HealthUploader._();
   static final HealthUploader instance = HealthUploader._();
@@ -32,7 +56,14 @@ class HealthUploader {
 
   /// Attempt an upload if [consented] AND on Wi-Fi AND charging AND >24h since the
   /// last one. Returns true if an upload actually happened.
+  ///
+  /// Defense in depth: even though the Settings/onboarding toggle that sets
+  /// [consented] is itself hidden when [kHealthDataContributionEnabled] is
+  /// false, gate the actual network call on the same flag directly — no
+  /// build without the flag should ever attempt this upload regardless of
+  /// how `consented` ended up true (e.g. a stale local pref).
   Future<bool> maybeUpload({required bool consented}) async {
+    if (!kHealthDataContributionEnabled) return false;
     if (!consented || !CompanionClient.configured || _running) return false;
     if (deviceId == null) return false;
     _running = true;
diff --git a/lib/ui/coach/coach_settings_screen.dart b/lib/ui/coach/coach_settings_screen.dart
index 38910b4e..881706ad 100644
--- a/lib/ui/coach/coach_settings_screen.dart
+++ b/lib/ui/coach/coach_settings_screen.dart
@@ -73,11 +73,19 @@ class _CoachSettingsScreenState extends State<CoachSettingsScreen> {
       setState(() => _msg = 'Pick or type a model first.');
       return;
     }
+    // Capture the messenger + navigator BEFORE the await (no BuildContext across
+    // an async gap), then guard pop() with canPop(): a bare Navigator.pop() after
+    // the await crashed with "Bad state: No element" (NavigatorState.pop's
+    // internal lastWhere) when the route was no longer poppable by the time save
+    // completed — being `mounted` doesn't guarantee a poppable route.
+    final messenger = ScaffoldMessenger.of(context);
+    final navigator = Navigator.of(context);
     await cfg.save(baseUrl: _base.text, apiKey: _key.text, model: _chosen);
-    if (mounted) {
-      ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text('AI Coach settings saved.')));
-      Navigator.of(context).pop();
-    }
+    if (!mounted) return;
+    messenger.showSnackBar(
+      const SnackBar(content: Text('AI Coach settings saved.')),
+    );
+    if (navigator.canPop()) navigator.pop();
   }
 
   // Searchable list of fetched models + a "use what I typed" custom row. The row
diff --git a/lib/ui/insights/coach_cards.dart b/lib/ui/insights/coach_cards.dart
index 7add2d61..3053fd83 100644
--- a/lib/ui/insights/coach_cards.dart
+++ b/lib/ui/insights/coach_cards.dart
@@ -1,5 +1,5 @@
 // Coach + fitness cards — surface the cross-day coaching/fitness analytics
-// (Sleep Coach, Strain Coach, WHOOP-Age) and the journal correlation engine
+// (Sleep Coach, Strain Coach, Fitness Age) and the journal correlation engine
 // ("Performance Assessment"). All read the precomputed `crossday` bundle via
 // repo.getInsights() (or getJournalInsights), so they do ZERO heavy compute on
 // read. Honest: every value traces to a tested analytics Metric; absent → a
@@ -276,16 +276,16 @@ class _StrainCoachCardState extends State<StrainCoachCard> {
   }
 }
 
-// ── WHOOP-AGE / fitness ──────────────────────────────────────────────────────
+// ── FITNESS AGE ──────────────────────────────────────────────────────────────
 
 /// Physiological "age" vs chronological + VO₂max estimate.
-class WhoopAgeCard extends StatefulWidget {
-  const WhoopAgeCard({super.key});
+class FitnessAgeCard extends StatefulWidget {
+  const FitnessAgeCard({super.key});
   @override
-  State<WhoopAgeCard> createState() => _WhoopAgeCardState();
+  State<FitnessAgeCard> createState() => _FitnessAgeCardState();
 }
 
-class _WhoopAgeCardState extends State<WhoopAgeCard> {
+class _FitnessAgeCardState extends State<FitnessAgeCard> {
   Map<String, dynamic>? _age;
   num? _vo2;
   bool _loading = true;
@@ -301,7 +301,7 @@ class _WhoopAgeCardState extends State<WhoopAgeCard> {
       final cd = await context.read<AppState>().repo?.getInsights();
       if (!mounted) return;
       setState(() {
-        _age = _val(cd?['whoop_age']);
+        _age = _val(cd?['fitness_age']);
         final v = cd?['vo2max'];
         _vo2 = v is Map ? v['value'] as num? : null;
         _loading = false;
diff --git a/lib/ui/kit/route_map.dart b/lib/ui/kit/route_map.dart
index 43b1f0cb..e03dafee 100644
--- a/lib/ui/kit/route_map.dart
+++ b/lib/ui/kit/route_map.dart
@@ -129,6 +129,16 @@ class RouteMapView extends StatelessWidget {
   /// look under the crisp line — the only colour against the monochrome
   /// basemap, so it needs to read as unmistakably "the route", not a thin
   /// GPS-app line lost against a busy street atlas.
+  // A bad GPS fix can carry NaN/Inf lat/lng (see the finite-filter in build()
+  // below for the camera/bounds path). _points there is filtered, but
+  // _polylines() reads straight from `vertices`, so it needs its own check —
+  // an unfiltered NaN/Inf vertex reaching PolylineLayer can crash or corrupt
+  // rendering.
+  bool _validPos(List<RouteVertex> v, int i) {
+    final p = v[i].pos;
+    return p.latitude.isFinite && p.longitude.isFinite;
+  }
+
   List<Polyline> _polylines({bool glow = false}) {
     final v = vertices;
     if (v.length < 2) return const [];
@@ -137,14 +147,19 @@ class RouteMapView extends StatelessWidget {
     final width = interactive ? 5.0 : 4.0;
     var i = 0;
     while (i < v.length - 1) {
-      if (v[i + 1].gapBefore) {
-        i++; // segment break — no edge across the gap
+      if (v[i + 1].gapBefore || !_validPos(v, i) || !_validPos(v, i + 1)) {
+        // Segment break — no edge across a recording gap OR an invalid
+        // (NaN/Inf) vertex; either way we never draw an edge touching it.
+        i++;
         continue;
       }
       final c = edgeColor(i);
       final pts = <LatLng>[v[i].pos];
       var j = i;
-      while (j < v.length - 1 && edgeColor(j) == c && !v[j + 1].gapBefore) {
+      while (j < v.length - 1 &&
+          edgeColor(j) == c &&
+          !v[j + 1].gapBefore &&
+          _validPos(v, j + 1)) {
         pts.add(v[j + 1].pos);
         j++;
       }
@@ -162,7 +177,13 @@ class RouteMapView extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
-    final pts = _points;
+    // Drop any non-finite GPS coordinate (a bad fix can carry NaN/Inf lat/lng).
+    // Left in, it makes LatLngBounds + camera-fit NaN and crashes the tile layer
+    // at build (NaN.toInt in flutter_map's _clampToNativeZoom) — a real FATAL.
+    final pts = [
+      for (final p in _points)
+        if (p.latitude.isFinite && p.longitude.isFinite) p,
+    ];
     if (pts.isEmpty) return const SizedBox.shrink();
 
     // Detect gesture-driven camera moves so a live map can stop auto-following.
@@ -170,10 +191,22 @@ class RouteMapView extends StatelessWidget {
       if (hasGesture) onUserPan?.call();
     }
 
-    final options = pts.length >= 2
+    // Only bounds-fit when the box has real area. A zero-area box (every point
+    // identical — a stationary or aborted route) makes CameraFit.bounds emit a
+    // NaN/Infinite zoom that the tile layer then crashes on; fall back to a
+    // fixed-zoom center view in that case.
+    LatLngBounds? fitBounds;
+    if (pts.length >= 2) {
+      final b = LatLngBounds.fromPoints(pts);
+      if ((b.north - b.south).abs() > 1e-7 ||
+          (b.east - b.west).abs() > 1e-7) {
+        fitBounds = b;
+      }
+    }
+    final options = fitBounds != null
         ? MapOptions(
             initialCameraFit: CameraFit.bounds(
-              bounds: LatLngBounds.fromPoints(pts),
+              bounds: fitBounds,
               padding: const EdgeInsets.all(28),
               // Cap how far bounds-fit will zoom in. Without this, a route
               // whose points are all still close together (early in a
diff --git a/lib/ui/onboarding/welcome_screen.dart b/lib/ui/onboarding/welcome_screen.dart
index 4005cbce..3ba3f51a 100644
--- a/lib/ui/onboarding/welcome_screen.dart
+++ b/lib/ui/onboarding/welcome_screen.dart
@@ -154,6 +154,8 @@ class _WelcomeScreenState extends State<WelcomeScreen> {
       physics: const BouncingScrollPhysics(),
       children: dsStaggered([
         const WelcomeHero(),
+        const SizedBox(height: Sp.x4),
+        const AffiliationDisclaimer(),
         const SizedBox(height: Sp.x6),
         Text('How do you want to start?', style: AppText.h2),
         const SizedBox(height: Sp.x4),
@@ -375,6 +377,24 @@ class WelcomeHero extends StatelessWidget {
   }
 }
 
+/// Legal/affiliation disclaimer shown once at first run (and mirrored in
+/// Settings → About — see [AboutScreen]). Attorney-reviewed wording; don't
+/// paraphrase without re-running it past the same review.
+class AffiliationDisclaimer extends StatelessWidget {
+  const AffiliationDisclaimer({super.key});
+
+  static const String text =
+      'Edge is an independent, open-source project. It is not affiliated '
+      'with, sponsored by, or endorsed by WHOOP, Inc. You must own a genuine '
+      'WHOOP 4.0 band to use this app. Health metrics are wellness estimates '
+      'from published research methods — not medical diagnoses.';
+
+  @override
+  Widget build(BuildContext context) {
+    return Text(text, style: AppText.captionMuted);
+  }
+}
+
 /// One onboarding choice — a SurfaceCard row: icon-in-tile, title, one quiet
 /// line, chevron. [accent] marks the recommended path with the ember tint.
 class WelcomeOptionCard extends StatelessWidget {
diff --git a/lib/ui/profile/about_screen.dart b/lib/ui/profile/about_screen.dart
new file mode 100644
index 00000000..8bbab5d5
--- /dev/null
+++ b/lib/ui/profile/about_screen.dart
@@ -0,0 +1,129 @@
+// about_screen.dart — Settings → About. Surfaces the affiliation/health-claim
+// disclaimer (same attorney-reviewed wording shown once at first run — see
+// AffiliationDisclaimer in lib/ui/onboarding/welcome_screen.dart), links to the
+// Privacy Policy and NOTICE, the open-source license attribution page, and the
+// installed app version. Added as part of app-store-readiness prep; the
+// disclaimer wording must not be edited without re-running it past legal
+// review.
+
+import 'package:flutter/material.dart';
+import 'package:package_info_plus/package_info_plus.dart';
+import 'package:url_launcher/url_launcher.dart';
+
+import '../design/design.dart';
+import '../onboarding/welcome_screen.dart' show AffiliationDisclaimer;
+
+/// Hosted Privacy Policy (GitHub Pages, docs/legal-site). Both app stores
+/// require a live hosted URL, not a repo file — this is that URL.
+const String kPrivacyPolicyUrl = 'https://openstrap.github.io/edge/privacy.html';
+
+const String kNoticeUrl =
+    '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/OpenStrap/edge/blob/main/NOTICE.md';
+
+class AboutScreen extends StatefulWidget {
+  const AboutScreen({super.key});
+
+  @override
+  State<AboutScreen> createState() => _AboutScreenState();
+}
+
+class _AboutScreenState extends State<AboutScreen> {
+  PackageInfo? _pkg;
+
+  @override
+  void initState() {
+    super.initState();
+    PackageInfo.fromPlatform().then((p) {
+      if (mounted) setState(() => _pkg = p);
+    });
+  }
+
+  /// Returns whether the launch actually succeeded. `launchUrl` can return
+  /// `false` without throwing (e.g. no handler for the URL) — callers here
+  /// (Privacy Policy / Notice links) are legal-disclosure surfaces, so a
+  /// failed launch must be surfaced to the user rather than swallowed.
+  static Future<bool> _openUrl(String url) async {
+    try {
+      return await launchUrl(Uri.parse(url), mode: LaunchMode.externalApplication);
+    } catch (_) {
+      return false;
+    }
+  }
+
+  Future<void> _openUrlWithFeedback(String url) async {
+    final ok = await _openUrl(url);
+    if (!ok && mounted) {
+      ScaffoldMessenger.of(context).showSnackBar(
+        const SnackBar(content: Text("Couldn't open the link.")),
+      );
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final versionLabel = _pkg == null
+        ? null
+        : '${_pkg!.version}+${_pkg!.buildNumber}';
+
+    return AppScaffold(
+      title: 'About',
+      children: [
+        const SizedBox(height: Sp.x4),
+        SurfaceCard(
+          padding: const EdgeInsets.all(Sp.x4),
+          child: const AffiliationDisclaimer(),
+        ),
+        const SizedBox(height: Sp.x6),
+        const SectionHeader('Legal'),
+        _SettingsCard(rows: [
+          ListRow(
+            icon: OsIcon.activity,
+            title: 'Privacy policy',
+            divider: true,
+            onTap: () => _openUrlWithFeedback(kPrivacyPolicyUrl),
+          ),
+          ListRow(
+            icon: OsIcon.activity,
+            title: 'Notice & attribution',
+            subtitle: 'Trademark + reverse-engineering disclosure',
+            divider: true,
+            onTap: () => _openUrlWithFeedback(kNoticeUrl),
+          ),
+          ListRow(
+            icon: OsIcon.activity,
+            title: 'Open-source licenses',
+            onTap: () => showLicensePage(
+              context: context,
+              applicationName: 'Edge',
+              applicationVersion: versionLabel,
+            ),
+          ),
+        ]),
+        const SizedBox(height: Sp.x6),
+        const SectionHeader('Version'),
+        _SettingsCard(rows: [
+          ListRow(
+            icon: OsIcon.activity,
+            title: 'Edge',
+            value: versionLabel ?? '…',
+          ),
+        ]),
+        const SizedBox(height: Sp.x8),
+      ],
+    );
+  }
+}
+
+/// Local copy of ProfileScreen's private `_SettingsCard` shape (a SurfaceCard
+/// wrapping stacked ListRows) — kept tiny and duplicated rather than exporting
+/// the private widget across files for one screen.
+class _SettingsCard extends StatelessWidget {
+  final List<ListRow> rows;
+  const _SettingsCard({required this.rows});
+
+  @override
+  Widget build(BuildContext context) => SurfaceCard(
+        padding: const EdgeInsets.symmetric(horizontal: Sp.x4, vertical: Sp.x1),
+        child: Column(children: rows),
+      );
+}
diff --git a/lib/ui/profile/profile_screen.dart b/lib/ui/profile/profile_screen.dart
index 0431efe5..a6343000 100644
--- a/lib/ui/profile/profile_screen.dart
+++ b/lib/ui/profile/profile_screen.dart
@@ -19,12 +19,14 @@ import '../../health/health_export.dart';
 import '../../state/app_state.dart';
 import '../../state/units_controller.dart';
 import '../../debug/debug_mode.dart';
+import '../../telemetry/health_uploader.dart' show kHealthDataContributionEnabled;
 import '../../theme/theme_switcher.dart';
 import '../ai/ai_settings_screen.dart';
 import '../design/design.dart';
 import '../design/gallery_screen.dart';
 import '../import/import_screen.dart';
 import '../today/step_goal_screen.dart';
+import 'about_screen.dart';
 import 'advanced_data_screen.dart';
 import 'data_history_screen.dart';
 import 'gesture_section.dart';
@@ -323,17 +325,24 @@ class ProfileScreen extends StatelessWidget {
             value: app.telemetryConsent,
             onChanged: (v) => app.setTelemetryConsent(v),
           ),
-          const SizedBox(height: Sp.x3),
-          _ToggleCard(
-            icon: OsIcon.activity,
-            title: 'Contribute my health data',
-            subtitle:
-                'Periodically upload your on-device database (over Wi-Fi, '
-                'while charging) to improve the algorithms. On by default — '
-                'switch off anytime.',
-            value: app.healthShareConsent,
-            onChanged: (v) => app.setHealthShareConsent(v),
-          ),
+          // Health-data contribution (full on-device DB upload) is a
+          // compile-time-gated feature (see kHealthDataContributionEnabled) —
+          // never offered in a store-review-facing build, only in a
+          // sideload/direct-distribution build that opted in. Hide the
+          // toggle entirely rather than leave it visible-but-inert.
+          if (kHealthDataContributionEnabled) ...[
+            const SizedBox(height: Sp.x3),
+            _ToggleCard(
+              icon: OsIcon.activity,
+              title: 'Contribute my health data',
+              subtitle:
+                  'Periodically upload your on-device database (over Wi-Fi, '
+                  'while charging) to improve the algorithms. On by default — '
+                  'switch off anytime.',
+              value: app.healthShareConsent,
+              onChanged: (v) => app.setHealthShareConsent(v),
+            ),
+          ],
 
           const SizedBox(height: Sp.x6),
 
@@ -422,6 +431,20 @@ class ProfileScreen extends StatelessWidget {
 
           const SizedBox(height: Sp.x6),
 
+          // ── About ────────────────────────────────────────────────────
+          const SectionHeader('About'),
+          _SettingsCard(rows: [
+            ListRow(
+              icon: OsIcon.activity,
+              title: 'About Edge',
+              subtitle: 'Affiliation, privacy policy, licenses',
+              onTap: () => Navigator.of(context).push(
+                  themedRoute((_) => const AboutScreen(), name: 'AboutScreen')),
+            ),
+          ]),
+
+          const SizedBox(height: Sp.x6),
+
           // ── Reset ────────────────────────────────────────────────────
           const SectionHeader('Reset'),
           _SettingsCard(rows: [
diff --git a/lib/ui/profile_setup_screen.dart b/lib/ui/profile_setup_screen.dart
index 1037099e..105a4025 100644
--- a/lib/ui/profile_setup_screen.dart
+++ b/lib/ui/profile_setup_screen.dart
@@ -16,6 +16,7 @@ import 'package:flutter/services.dart';
 import 'package:provider/provider.dart';
 
 import '../state/app_state.dart';
+import '../telemetry/health_uploader.dart' show kHealthDataContributionEnabled;
 import 'design/design.dart';
 
 class ProfileSetupScreen extends StatefulWidget {
@@ -30,7 +31,10 @@ class _ProfileSetupScreenState extends State<ProfileSetupScreen> {
   // either off here). Recorded + sent on Continue. When re-editing an existing
   // profile we reflect the saved choice instead.
   bool _telemetry = true;
-  bool _healthShare = true;
+  // Health-data contribution is a compile-time-gated feature (see
+  // kHealthDataContributionEnabled) — never pre-enabled (or even offered) in
+  // a build that doesn't carry it.
+  bool _healthShare = kHealthDataContributionEnabled;
 
   @override
   void initState() {
@@ -43,6 +47,10 @@ class _ProfileSetupScreenState extends State<ProfileSetupScreen> {
       _telemetry = app.telemetryConsent;
       _healthShare = app.healthShareConsent;
     }
+    // Never true in a build without the feature — even a stale saved `true`
+    // (e.g. carried over from a different build's local prefs) must not
+    // resubmit consent for an upload this build will never attempt.
+    if (!kHealthDataContributionEnabled) _healthShare = false;
   }
 
   Future<void> _submit(
@@ -84,7 +92,9 @@ class ProfileSetupForm extends StatefulWidget {
     super.key,
     this.initial = const {},
     this.telemetryInitial = true,
-    this.healthShareInitial = true,
+    // Gated default: never pre-enabled (or shown) in a build compiled
+    // without kHealthDataContributionEnabled.
+    this.healthShareInitial = kHealthDataContributionEnabled,
     required this.onSubmit,
   });
 
@@ -207,18 +217,25 @@ class _ProfileSetupFormState extends State<ProfileSetupForm> {
           value: _telemetry,
           onChanged: (v) => setState(() => _telemetry = v),
         ),
-        const SizedBox(height: Sp.x3),
-        ConsentTile(
-          title: 'Contribute my health data',
-          subtitle:
-              'Uploads your on-device database over Wi-Fi while charging, to '
-              'improve the algorithms.',
-          value: _healthShare,
-          onChanged: (v) => setState(() => _healthShare = v),
-        ),
+        // Health-data contribution (full on-device DB upload) is a
+        // compile-time-gated feature (see kHealthDataContributionEnabled) —
+        // never offered in a store-review-facing build.
+        if (kHealthDataContributionEnabled) ...[
+          const SizedBox(height: Sp.x3),
+          ConsentTile(
+            title: 'Contribute my health data',
+            subtitle:
+                'Uploads your on-device database over Wi-Fi while charging, '
+                'to improve the algorithms.',
+            value: _healthShare,
+            onChanged: (v) => setState(() => _healthShare = v),
+          ),
+        ],
         const SizedBox(height: Sp.x2),
         Text(
-          'Switch either off here or anytime in Settings.',
+          kHealthDataContributionEnabled
+              ? 'Switch either off here or anytime in Settings.'
+              : 'Switch it off here or anytime in Settings.',
           style: AppText.caption.copyWith(color: AppColors.inkMuted),
         ),
         const SizedBox(height: Sp.x7),
diff --git a/lib/ui/screens/screens.dart b/lib/ui/screens/screens.dart
index 362f98fc..93acdeab 100644
--- a/lib/ui/screens/screens.dart
+++ b/lib/ui/screens/screens.dart
@@ -148,7 +148,7 @@ class BodyScreen extends StatelessWidget {
         const SizedBox(height: Sp.x3),
         StrainDetailScreen(date: todayLabel(), embedded: true),
         const SizedBox(height: Sp.x3),
-        const WhoopAgeCard(),
+        const FitnessAgeCard(),
         const SizedBox(height: Sp.x3),
         const PerformanceAssessmentCard(),
         const CycleEntryCard(),
diff --git a/pubspec.yaml b/pubspec.yaml
index 8db63312..5a5ab5b9 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,6 +1,11 @@
 name: openstrap_edge
-description: "OpenStrap — open-source WHOOP 4.0 companion. BLE drain → raw-first local store → cloud sync."
+description: "Open-source, local-first fitness tracking companion for WHOOP 4.0 hardware. Not affiliated with WHOOP, Inc."
 publish_to: 'none'
+# NOTE: bumping this also requires manually bumping MARKETING_VERSION/
+# CURRENT_PROJECT_VERSION for the OpenStrapWidget(Extension) and "OpenStrapWatch
+# Watch App" targets in ios/Runner.xcodeproj/project.pbxproj — they aren't wired
+# to FLUTTER_BUILD_NAME/FLUTTER_BUILD_NUMBER. See guides/IOS_INSTALLATION.md
+# "Version Numbers".
 version: 0.9.14+47
 
 environment:
diff --git a/test/flow_screens_redesign_test.dart b/test/flow_screens_redesign_test.dart
index f4ca135f..9c0ebf08 100644
--- a/test/flow_screens_redesign_test.dart
+++ b/test/flow_screens_redesign_test.dart
@@ -14,6 +14,8 @@ import 'package:openstrap_edge/ui/onboarding/welcome_screen.dart'
     show WelcomeHero, WelcomeOptionCard;
 import 'package:openstrap_edge/ui/pairing_screen.dart'
     show PairPhase, PairingInstructionContent, PairingStateView;
+import 'package:openstrap_edge/telemetry/health_uploader.dart'
+    show kHealthDataContributionEnabled;
 import 'package:openstrap_edge/ui/profile/profile_screen.dart' show DeviceTile;
 import 'package:openstrap_edge/ui/profile_setup_screen.dart'
     show ConsentTile, ProfileSetupForm;
@@ -166,7 +168,12 @@ void main() {
       expect(find.text('About you'), findsOneWidget);
       expect(find.text('Male'), findsOneWidget);
       expect(find.text('Female'), findsOneWidget);
-      expect(find.byType(ConsentTile), findsNWidgets(2));
+      // The health-data-contribution tile only renders in a build compiled
+      // with kHealthDataContributionEnabled (never in CI/default test runs).
+      expect(
+        find.byType(ConsentTile),
+        findsNWidgets(kHealthDataContributionEnabled ? 2 : 1),
+      );
 
       // No sex chosen yet → Continue disabled (onSubmit not called on tap).
       await t.ensureVisible(find.text('Continue'));
@@ -186,7 +193,9 @@ void main() {
       expect(submitted!['age'], 30);
       expect(submitted!['sex'], 'f');
       expect(telemetry, isTrue);
-      expect(healthShare, isTrue);
+      // Gated default: only pre-enabled in a build compiled with
+      // kHealthDataContributionEnabled.
+      expect(healthShare, kHealthDataContributionEnabled);
     });
   }