UnifiedPush: reach a phone that has no Google in it.

Web push on Android is Firebase's, so a phone without Google Play Services —
GrapheneOS, CalyxOS, any de-Googled Android — cannot be woken by a web app at
all. UnifiedPush is the way that doesn't involve Google: the user runs a
distributor (ntfy and friends), apps ask it for an endpoint, and whoever
wants to reach the device POSTs to that endpoint.

THE WRAPPER speaks the protocol directly — four broadcasts each way, so it
pulls in no library; an APK this small has no business growing a Kotlin
runtime for eight intents. It asks the distributor on every launch (the call
is idempotent, and it's how a distributor installed later gets noticed),
raises a notification when a message arrives, and acknowledges it so the
distributor stops resending.

THE ENDPOINT reaches the web app on the launch URL as ?up=, the same road
payment intents already travel — because the distributor talks to the app and
only the web app knows which pubkeys are worth watching. It's registered with
the notifier in place of a browser subscription, for notifications and for
NWC alike, and needs neither permission nor push service.

THE NOTIFIER sends to either kind: one deliver() that POSTs the payload to a
UnifiedPush endpoint, or hands it to web-push as before. Same payloads, same
404/410 pruning. The endpoint is the only secret there, so it's never logged
in full.

Verified: a POST to a live ntfy endpoint delivers the payload byte for byte,
so the app parses exactly what the notifier sent; the APK builds, carries the
receiver, and is signed with the certificate assetlinks already pins (v1.6).
tools/unifiedpush-test.js drives a browser with no push service and checks
the endpoint is taken off the URL, kept, and registered.

Honest about the limit: a UnifiedPush message wakes the ANDROID app, not
Chrome's service worker, and the wallet's keys live in the browser's storage
where nothing here can reach them. So a zap request arrives as a notification
you tap, and the wallet answers when it opens — one tap instead of none.
Automatic answering while closed still needs a browser with a push service.

Co-Authored-By: Claude Opus 5 (1M context) <[email protected]>
Claude-Session: https://claude.ai/code/session_019mrt228Upn9nNCwGixzSLx

1 files changed, 22 insertions, 0 deletions

diff --git a/android/app/src/main/AndroidManifest.xml b/android/app/src/main/AndroidManifest.xml
index e2f4e16..36f9d1e 100644
--- a/android/app/src/main/AndroidManifest.xml
+++ b/android/app/src/main/AndroidManifest.xml
@@ -7,6 +7,15 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android">
   <!-- NFC is a way in (bolt cards, NDEF tags), never a requirement -->
   <uses-feature android:name="android.hardware.nfc" android:required="false" />
+  <!-- our own notifications, raised from UnifiedPush messages (Android 13+) -->
+  <uses-permission android:name="android.permission.POST_NOTIFICATIONS" />
+  <!-- Which apps can act as a UnifiedPush distributor: Android 11+ hides the
+       package list unless we say what we're looking for. -->
+  <queries>
+    <intent>
+      <action android:name="org.unifiedpush.android.distributor.REGISTER" />
+    </intent>
+  </queries>
   <application
       android:label="@string/app_name"
       android:icon="@mipmap/ic_launcher"
@@ -86,5 +95,18 @@
         <data android:scheme="https" android:host="v3.coinos.io" />
       </intent-filter>
     </activity>
+    <!-- UnifiedPush: the distributor broadcasts here. Web push needs Google
+         Play Services on Android, so on a de-Googled phone this is the only
+         way the wallet can be reached at all while it isn't open. -->
+    <receiver
+        android:name="io.coinos.app.PushReceiver"
+        android:exported="true">
+      <intent-filter>
+        <action android:name="org.unifiedpush.android.connector.NEW_ENDPOINT" />
+        <action android:name="org.unifiedpush.android.connector.REGISTRATION_FAILED" />
+        <action android:name="org.unifiedpush.android.connector.UNREGISTERED" />
+        <action android:name="org.unifiedpush.android.connector.MESSAGE" />
+      </intent-filter>
+    </receiver>
   </application>
 </manifest>