Point WEBSITE_URL back at production

Was pointed at kwaba-dev for testing while chasing the caching/icon
issues earlier this session. Production is confirmed caught up to the
same code already verified against kwaba-dev, and in-app updates now
mean future fixes won't require a manual reinstall anyway.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LHgWjmEJXsJEi1EVAoTp4K

app/build.gradle.kts

@@ -11,8 +11,8 @@ android {
         applicationId = "de.ggb.kwabatv"
         minSdk = 21
         targetSdk = 34
-        versionCode = 1
+        versionCode = 2
-        versionName = "1.0"
+        versionName = "1.1.0"
         buildConfigField("String", "WEBSITE_URL", "\"https://kwaba.whodovoodoo.pasteaf.de/tv\"")
     }
 
@@ -35,3 +35,11 @@ android {
         jvmTarget = "1.8"
     }
 }
+
+dependencies {
+    testImplementation("junit:junit:4.13.2")
+    // Android's org.json classes are stubbed out (throw at runtime) in plain JVM unit
+    // tests unless a real implementation is on the test classpath - this is that
+    // implementation, test-only, never shipped in the APK.
+    testImplementation("org.json:json:20231013")
+}

app/src/main/AndroidManifest.xml

@@ -2,13 +2,14 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android">
 
     <uses-permission android:name="android.permission.INTERNET" />
+    <uses-permission android:name="android.permission.REQUEST_INSTALL_PACKAGES" />
     <uses-feature android:name="android.software.leanback" android:required="false" />
     <uses-feature android:name="android.hardware.touchscreen" android:required="false" />
 
     <application
         android:allowBackup="true"
-        android:icon="@drawable/ic_launcher_art"
+        android:icon="@mipmap/ic_launcher_art"
-        android:banner="@drawable/banner_tv_art"
+        android:banner="@mipmap/banner_tv_art"
         android:label="@string/app_name"
         android:networkSecurityConfig="@xml/network_security_config"
         android:theme="@android:style/Theme.NoTitleBar.Fullscreen">

app/src/main/java/de/ggb/kwabatv/MainActivity.kt

@@ -1,9 +1,17 @@
 package de.ggb.kwabatv
 
 import android.app.Activity
+import android.app.AlertDialog
+import android.app.DownloadManager
+import android.content.BroadcastReceiver
+import android.content.Context
+import android.content.Intent
+import android.content.IntentFilter
 import android.net.Uri
+import android.os.Build
 import android.os.Bundle
 import android.os.SystemClock
+import android.provider.Settings
 import android.view.KeyEvent
 import android.view.View
 import android.webkit.PermissionRequest
@@ -49,6 +57,8 @@ class MainActivity : Activity() {
     private var fullscreenView: View? = null
     private var currentPath: String = "/tv"
     private var lastThrottledSeekAt = 0L
+    private var pendingDownloadId: Long = -1
+    private var receiverRegistered = false
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
@@ -84,13 +94,92 @@ class MainActivity : Activity() {
         }
 
         webView.loadUrl(BuildConfig.WEBSITE_URL)
+        checkForUpdateInBackground()
     }
 
     override fun onDestroy() {
         webView.destroy()
+        if (receiverRegistered) { unregisterReceiver(downloadReceiver); receiverRegistered = false }
         super.onDestroy()
     }
 
+    /* ---------------------------------------------------------- In-App-Update
+       Prueft bei jedem Start das oeffentliche KwabaTV-Gitea-Repo auf ein neueres
+       Release (siehe UpdateChecker.kt) und bietet es ueber Androids eigenen
+       Paket-Installer an - nie ohne Bestaetigung, das Betriebssystem selbst
+       erlaubt keine stille Installation. Ein fehlgeschlagener Check ist immer
+       lautlos: kein Fehlerdialog, einfach beim naechsten Start erneut versuchen. */
+
+    private fun checkForUpdateInBackground() {
+        Thread {
+            val update = UpdateChecker.checkForUpdate(BuildConfig.VERSION_NAME)
+            if (update != null) runOnUiThread { showUpdateDialog(update) }
+        }.start()
+    }
+
+    private fun showUpdateDialog(update: UpdateInfo) {
+        AlertDialog.Builder(this)
+            .setTitle("Update verfügbar")
+            .setMessage("KwabaTV v${update.version} ist verfügbar.")
+            .setPositiveButton("Aktualisieren") { _, _ -> startUpdate(update) }
+            .setNegativeButton("Später", null)
+            .show()
+    }
+
+    /* "Unbekannte Apps installieren" ist fuer neue Apps ab Android 8 (API 26)
+       pro App einzeln zu erlauben - ohne das wuerde der Installations-Intent
+       unten stillschweigend nichts tun. Statt automatisch nach der Rueckkehr
+       aus den Einstellungen weiterzumachen (mehr Zustand, mehr Fehlerquellen),
+       muss der Nutzer "Aktualisieren" nach dem Erlauben schlicht erneut
+       druecken - siehe Design-Spec. */
+    private fun startUpdate(update: UpdateInfo) {
+        val canInstall = Build.VERSION.SDK_INT < Build.VERSION_CODES.O || packageManager.canRequestPackageInstalls()
+        if (!canInstall) {
+            startActivity(Intent(Settings.ACTION_MANAGE_UNKNOWN_APP_SOURCES, Uri.parse("package:$packageName")))
+            return
+        }
+        downloadApk(update.apkDownloadUrl)
+    }
+
+    private fun downloadApk(url: String) {
+        val request = DownloadManager.Request(Uri.parse(url))
+            .setTitle("KwabaTV Update")
+            .setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED)
+            .setDestinationInExternalFilesDir(this, null, "KwabaTV-update.apk")
+        val downloadManager = getSystemService(DOWNLOAD_SERVICE) as DownloadManager
+        pendingDownloadId = downloadManager.enqueue(request)
+        // Ab Android 13 (API 33) muss jeder dynamisch registrierte Receiver
+        // explizit als (nicht-)exportiert markiert sein, sonst wirft
+        // registerReceiver() eine SecurityException.
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU) {
+            registerReceiver(downloadReceiver, IntentFilter(DownloadManager.ACTION_DOWNLOAD_COMPLETE), Context.RECEIVER_NOT_EXPORTED)
+        } else {
+            @Suppress("UnspecifiedRegisterReceiverFlag")
+            registerReceiver(downloadReceiver, IntentFilter(DownloadManager.ACTION_DOWNLOAD_COMPLETE))
+        }
+        receiverRegistered = true
+    }
+
+    private val downloadReceiver = object : BroadcastReceiver() {
+        override fun onReceive(context: Context, intent: Intent) {
+            if (intent.getLongExtra(DownloadManager.EXTRA_DOWNLOAD_ID, -1) != pendingDownloadId) return
+            if (receiverRegistered) { unregisterReceiver(this); receiverRegistered = false }
+            val downloadManager = getSystemService(DOWNLOAD_SERVICE) as DownloadManager
+            // getUriForDownloadedFile() returns null for a failed download - that failure is
+            // silent for now too, matching the update check's own error handling (see spec).
+            val uri = downloadManager.getUriForDownloadedFile(pendingDownloadId) ?: return
+            installApk(uri)
+        }
+    }
+
+    private fun installApk(uri: Uri) {
+        val intent = Intent(Intent.ACTION_VIEW).apply {
+            setDataAndType(uri, "application/vnd.android.package-archive")
+            addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
+        }
+        startActivity(intent)
+    }
+
     private fun isRoomList() = currentPath == "/tv"
     private fun isInRoom() = currentPath.startsWith("/tv/")
 

app/src/main/java/de/ggb/kwabatv/UpdateChecker.kt

@@ -0,0 +1,90 @@
+package de.ggb.kwabatv
+
+import org.json.JSONArray
+import java.net.HttpURLConnection
+import java.net.URL
+
+/** A qualifying update found on Gitea: display version and the APK's direct download URL. */
+data class UpdateInfo(val version: String, val apkDownloadUrl: String)
+
+/**
+ * Checks the public KwabaTV Gitea repo for a newer release. Fully self-contained - no
+ * kwaba-sync server involvement, since GGB/KwabaTV is a public repo and its releases API
+ * needs no authentication. See docs/superpowers/specs/2026-09-27-in-app-updates-design.md.
+ */
+object UpdateChecker {
+    private const val RELEASES_API_URL = "https://git.whodovoodoo.de/api/v1/repos/GGB/KwabaTV/releases"
+    private const val DOWNLOAD_BASE_URL = "https://git.whodovoodoo.de/GGB/KwabaTV/releases/download"
+    private const val ASSET_NAME = "KwabaTV.apk"
+    private val VERSION_RE = Regex("""^(\d+)\.(\d+)\.(\d+)$""")
+
+    /** Parses a bare "X.Y.Z" version string (no "v" prefix) into [major, minor, patch], or null if malformed. */
+    fun parseVersion(version: String): List<Int>? {
+        val m = VERSION_RE.matchEntire(version) ?: return null
+        return m.groupValues.drop(1).map { it.toInt() }
+    }
+
+    /** Positive if [a] is newer than [b], negative if older, 0 if equal. Both must be 3-element lists. */
+    fun compareVersions(a: List<Int>, b: List<Int>): Int {
+        for (i in 0..2) {
+            val diff = a[i] - b[i]
+            if (diff != 0) return diff
+        }
+        return 0
+    }
+
+    /**
+     * Picks the newest qualifying release from a Gitea releases API JSON array: not a draft,
+     * not a prerelease, tag matches "vX.Y.Z", newer than [currentVersion], and has a
+     * "KwabaTV.apk" asset. Returns null if none qualify or the JSON is malformed. The download
+     * URL is built manually from tag + asset name (same approach as kwaba-sync's own
+     * src/desktop-release.js) rather than trusting the API response's browser_download_url.
+     */
+    fun pickUpdate(releasesJson: String, currentVersion: String): UpdateInfo? {
+        val current = parseVersion(currentVersion) ?: return null
+        val releases = try { JSONArray(releasesJson) } catch (e: Exception) { return null }
+
+        var best: Pair<List<Int>, UpdateInfo>? = null
+        for (i in 0 until releases.length()) {
+            val release = releases.optJSONObject(i) ?: continue
+            if (release.optBoolean("draft", false) || release.optBoolean("prerelease", false)) continue
+
+            val tag = release.optString("tag_name", "")
+            if (!tag.startsWith("v")) continue
+            val version = parseVersion(tag.substring(1)) ?: continue
+            if (compareVersions(version, current) <= 0) continue
+
+            val assets = release.optJSONArray("assets") ?: continue
+            var hasApk = false
+            for (j in 0 until assets.length()) {
+                if (assets.optJSONObject(j)?.optString("name") == ASSET_NAME) { hasApk = true; break }
+            }
+            if (!hasApk) continue
+
+            if (best == null || compareVersions(version, best!!.first) > 0) {
+                best = version to UpdateInfo(version.joinToString("."), "$DOWNLOAD_BASE_URL/$tag/$ASSET_NAME")
+            }
+        }
+        return best?.second
+    }
+
+    /**
+     * Fetches the releases list and returns the newest qualifying update, or null - including
+     * on any failure (network unreachable, non-200 response, malformed body). An update check
+     * is a nice-to-have; it must never be able to crash or visibly disrupt normal app use.
+     */
+    fun checkForUpdate(currentVersion: String): UpdateInfo? {
+        return try {
+            val connection = URL(RELEASES_API_URL).openConnection() as HttpURLConnection
+            connection.connectTimeout = 8000
+            connection.readTimeout = 8000
+            connection.requestMethod = "GET"
+            connection.setRequestProperty("Accept", "application/json")
+            if (connection.responseCode != 200) return null
+            val body = connection.inputStream.bufferedReader().use { it.readText() }
+            pickUpdate(body, currentVersion)
+        } catch (e: Exception) {
+            null
+        }
+    }
+}

app/src/test/java/de/ggb/kwabatv/UpdateCheckerTest.kt

@@ -0,0 +1,137 @@
+package de.ggb.kwabatv
+
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertNull
+import org.junit.Assert.assertTrue
+import org.junit.Test
+
+class UpdateCheckerTest {
+
+    @Test
+    fun `parseVersion parses a valid three-part version`() {
+        assertEquals(listOf(1, 2, 3), UpdateChecker.parseVersion("1.2.3"))
+    }
+
+    @Test
+    fun `parseVersion rejects a two-part version`() {
+        assertNull(UpdateChecker.parseVersion("1.0"))
+    }
+
+    @Test
+    fun `parseVersion rejects a version with a v prefix`() {
+        assertNull(UpdateChecker.parseVersion("v1.2.3"))
+    }
+
+    @Test
+    fun `parseVersion rejects non-numeric input`() {
+        assertNull(UpdateChecker.parseVersion("a.b.c"))
+    }
+
+    @Test
+    fun `compareVersions is positive when a is newer in the minor position`() {
+        assertTrue(UpdateChecker.compareVersions(listOf(1, 1, 0), listOf(1, 0, 9)) > 0)
+    }
+
+    @Test
+    fun `compareVersions is negative when a is older in the patch position`() {
+        assertTrue(UpdateChecker.compareVersions(listOf(1, 0, 0), listOf(1, 0, 1)) < 0)
+    }
+
+    @Test
+    fun `compareVersions is zero for equal versions`() {
+        assertEquals(0, UpdateChecker.compareVersions(listOf(2, 3, 4), listOf(2, 3, 4)))
+    }
+
+    @Test
+    fun `pickUpdate returns the newer release when one qualifies`() {
+        val json = """
+            [
+              {
+                "tag_name": "v1.1.0",
+                "draft": false,
+                "prerelease": false,
+                "assets": [ { "name": "KwabaTV.apk" } ]
+              }
+            ]
+        """.trimIndent()
+        val result = UpdateChecker.pickUpdate(json, "1.0.0")
+        assertEquals(
+            UpdateInfo("1.1.0", "https://git.whodovoodoo.de/GGB/KwabaTV/releases/download/v1.1.0/KwabaTV.apk"),
+            result
+        )
+    }
+
+    @Test
+    fun `pickUpdate returns null when the release is not newer`() {
+        val json = """
+            [
+              { "tag_name": "v1.0.0", "draft": false, "prerelease": false,
+                "assets": [ { "name": "KwabaTV.apk" } ] }
+            ]
+        """.trimIndent()
+        assertNull(UpdateChecker.pickUpdate(json, "1.0.0"))
+    }
+
+    @Test
+    fun `pickUpdate skips draft releases`() {
+        val json = """
+            [
+              { "tag_name": "v9.9.9", "draft": true, "prerelease": false,
+                "assets": [ { "name": "KwabaTV.apk" } ] }
+            ]
+        """.trimIndent()
+        assertNull(UpdateChecker.pickUpdate(json, "1.0.0"))
+    }
+
+    @Test
+    fun `pickUpdate skips prerelease releases`() {
+        val json = """
+            [
+              { "tag_name": "v9.9.9", "draft": false, "prerelease": true,
+                "assets": [ { "name": "KwabaTV.apk" } ] }
+            ]
+        """.trimIndent()
+        assertNull(UpdateChecker.pickUpdate(json, "1.0.0"))
+    }
+
+    @Test
+    fun `pickUpdate skips a release with no matching apk asset`() {
+        val json = """
+            [
+              { "tag_name": "v1.1.0", "draft": false, "prerelease": false,
+                "assets": [ { "name": "checksums.txt" } ] }
+            ]
+        """.trimIndent()
+        assertNull(UpdateChecker.pickUpdate(json, "1.0.0"))
+    }
+
+    @Test
+    fun `pickUpdate returns null for malformed json`() {
+        assertNull(UpdateChecker.pickUpdate("not json", "1.0.0"))
+    }
+
+    @Test
+    fun `pickUpdate returns null when currentVersion itself is malformed`() {
+        val json = """
+            [
+              { "tag_name": "v1.1.0", "draft": false, "prerelease": false,
+                "assets": [ { "name": "KwabaTV.apk" } ] }
+            ]
+        """.trimIndent()
+        assertNull(UpdateChecker.pickUpdate(json, "not-a-version"))
+    }
+
+    @Test
+    fun `pickUpdate picks the highest of multiple qualifying releases`() {
+        val json = """
+            [
+              { "tag_name": "v1.1.0", "draft": false, "prerelease": false,
+                "assets": [ { "name": "KwabaTV.apk" } ] },
+              { "tag_name": "v1.2.0", "draft": false, "prerelease": false,
+                "assets": [ { "name": "KwabaTV.apk" } ] }
+            ]
+        """.trimIndent()
+        val result = UpdateChecker.pickUpdate(json, "1.0.0")
+        assertEquals("1.2.0", result?.version)
+    }
+}

docs/superpowers/plans/2026-09-27-in-app-updates.md

@@ -0,0 +1,652 @@
+# In-App Updates Implementation Plan
+
+> **For agentic workers:** REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (`- [ ]`) syntax for tracking.
+
+**Goal:** KwabaTV checks its public Gitea repo for a newer release on every launch and, with explicit user confirmation, downloads and installs it via Android's own system package installer.
+
+**Architecture:** Fully self-contained in the kwabatv repo — no `kwaba-sync` server involvement, since `GGB/KwabaTV` is a public Gitea repo and its releases API needs no authentication. A pure, unit-tested version-comparison core (`UpdateChecker`) is wrapped by a real network fetch, then wired into `MainActivity` via a native `AlertDialog` and Android's `DownloadManager` + system package installer.
+
+**Tech Stack:** Kotlin, Android base SDK only (`org.json`, `java.net.HttpURLConnection`, `android.app.DownloadManager` — no new runtime dependencies), JUnit4 + `org.json:json` as test-only dependencies for local unit tests.
+
+## Global Constraints
+
+- No AndroidX dependencies — matches the project's existing zero-dependency, WebView-only design (see `docs/superpowers/specs/2026-09-27-in-app-updates-design.md`). This is why the plan uses `DownloadManager` instead of a custom `FileProvider`.
+- Release tag convention: `vX.Y.Z` (e.g. `v1.1.0`). APK asset name is always exactly `KwabaTV.apk`.
+- Never install silently — Android's system package installer always requires an explicit user tap, by OS design. Nothing in this plan attempts to bypass that.
+- Update-check failures (network unreachable, malformed JSON, no qualifying release) are always silent — no error dialog, no toast. Just try again next launch.
+- `JAVA_HOME` for every Gradle command in this plan: `/c/Users/GGB/jdks/jdk-21.0.12.1+1` (Gradle 8.7 does not run on JDK 25, which is what Android Studio's bundled JBR ships).
+- Build/install verification throughout uses the existing project pattern: `cd /c/Projekte/kwabatv && JAVA_HOME="/c/Users/GGB/jdks/jdk-21.0.12.1+1" ./gradlew.bat <task>`.
+
+---
+
+### Task 1: Pure version-comparison logic, fully unit-tested
+
+**Files:**
+- Modify: `app/build.gradle.kts` (add a `dependencies` block — none exists yet)
+- Create: `app/src/main/java/de/ggb/kwabatv/UpdateChecker.kt`
+- Create: `app/src/test/java/de/ggb/kwabatv/UpdateCheckerTest.kt` (new source set — `src/test/java` doesn't exist yet in this project, Gradle picks it up automatically once it exists alongside a test dependency)
+
+**Interfaces:**
+- Produces: `data class UpdateInfo(val version: String, val apkDownloadUrl: String)` — top-level in `UpdateChecker.kt`, package `de.ggb.kwabatv` (no import needed from `MainActivity.kt`, same package).
+- Produces: `object UpdateChecker` with `fun parseVersion(version: String): List<Int>?`, `fun compareVersions(a: List<Int>, b: List<Int>): Int`, `fun pickUpdate(releasesJson: String, currentVersion: String): UpdateInfo?`. Task 2 adds a fourth function, `checkForUpdate`, to this same object.
+
+- [ ] **Step 1: Add test dependencies to `app/build.gradle.kts`**
+
+Current file ends with:
+```kotlin
+    kotlinOptions {
+        jvmTarget = "1.8"
+    }
+}
+```
+
+Add a `dependencies` block directly after the closing `}` of the `android { ... }` block (i.e. at the very end of the file):
+
+```kotlin
+    kotlinOptions {
+        jvmTarget = "1.8"
+    }
+}
+
+dependencies {
+    testImplementation("junit:junit:4.13.2")
+    // Android's org.json classes are stubbed out (throw at runtime) in plain JVM unit
+    // tests unless a real implementation is on the test classpath - this is that
+    // implementation, test-only, never shipped in the APK.
+    testImplementation("org.json:json:20231013")
+}
+```
+
+- [ ] **Step 2: Create `UpdateChecker.kt` with stub implementations (so the test file below compiles, but fails on assertions)**
+
+Create `app/src/main/java/de/ggb/kwabatv/UpdateChecker.kt`:
+
+```kotlin
+package de.ggb.kwabatv
+
+/** A qualifying update found on Gitea: display version and the APK's direct download URL. */
+data class UpdateInfo(val version: String, val apkDownloadUrl: String)
+
+/**
+ * Checks the public KwabaTV Gitea repo for a newer release. Fully self-contained - no
+ * kwaba-sync server involvement, since GGB/KwabaTV is a public repo and its releases API
+ * needs no authentication. See docs/superpowers/specs/2026-09-27-in-app-updates-design.md.
+ */
+object UpdateChecker {
+
+    fun parseVersion(version: String): List<Int>? = null
+
+    fun compareVersions(a: List<Int>, b: List<Int>): Int = 0
+
+    fun pickUpdate(releasesJson: String, currentVersion: String): UpdateInfo? = null
+}
+```
+
+- [ ] **Step 3: Write the test file**
+
+Create `app/src/test/java/de/ggb/kwabatv/UpdateCheckerTest.kt`:
+
+```kotlin
+package de.ggb.kwabatv
+
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertNull
+import org.junit.Assert.assertTrue
+import org.junit.Test
+
+class UpdateCheckerTest {
+
+    @Test
+    fun `parseVersion parses a valid three-part version`() {
+        assertEquals(listOf(1, 2, 3), UpdateChecker.parseVersion("1.2.3"))
+    }
+
+    @Test
+    fun `parseVersion rejects a two-part version`() {
+        assertNull(UpdateChecker.parseVersion("1.0"))
+    }
+
+    @Test
+    fun `parseVersion rejects a version with a v prefix`() {
+        assertNull(UpdateChecker.parseVersion("v1.2.3"))
+    }
+
+    @Test
+    fun `parseVersion rejects non-numeric input`() {
+        assertNull(UpdateChecker.parseVersion("a.b.c"))
+    }
+
+    @Test
+    fun `compareVersions is positive when a is newer in the minor position`() {
+        assertTrue(UpdateChecker.compareVersions(listOf(1, 1, 0), listOf(1, 0, 9)) > 0)
+    }
+
+    @Test
+    fun `compareVersions is negative when a is older in the patch position`() {
+        assertTrue(UpdateChecker.compareVersions(listOf(1, 0, 0), listOf(1, 0, 1)) < 0)
+    }
+
+    @Test
+    fun `compareVersions is zero for equal versions`() {
+        assertEquals(0, UpdateChecker.compareVersions(listOf(2, 3, 4), listOf(2, 3, 4)))
+    }
+
+    @Test
+    fun `pickUpdate returns the newer release when one qualifies`() {
+        val json = """
+            [
+              {
+                "tag_name": "v1.1.0",
+                "draft": false,
+                "prerelease": false,
+                "assets": [ { "name": "KwabaTV.apk" } ]
+              }
+            ]
+        """.trimIndent()
+        val result = UpdateChecker.pickUpdate(json, "1.0.0")
+        assertEquals(
+            UpdateInfo("1.1.0", "https://git.whodovoodoo.de/GGB/KwabaTV/releases/download/v1.1.0/KwabaTV.apk"),
+            result
+        )
+    }
+
+    @Test
+    fun `pickUpdate returns null when the release is not newer`() {
+        val json = """
+            [
+              { "tag_name": "v1.0.0", "draft": false, "prerelease": false,
+                "assets": [ { "name": "KwabaTV.apk" } ] }
+            ]
+        """.trimIndent()
+        assertNull(UpdateChecker.pickUpdate(json, "1.0.0"))
+    }
+
+    @Test
+    fun `pickUpdate skips draft releases`() {
+        val json = """
+            [
+              { "tag_name": "v9.9.9", "draft": true, "prerelease": false,
+                "assets": [ { "name": "KwabaTV.apk" } ] }
+            ]
+        """.trimIndent()
+        assertNull(UpdateChecker.pickUpdate(json, "1.0.0"))
+    }
+
+    @Test
+    fun `pickUpdate skips prerelease releases`() {
+        val json = """
+            [
+              { "tag_name": "v9.9.9", "draft": false, "prerelease": true,
+                "assets": [ { "name": "KwabaTV.apk" } ] }
+            ]
+        """.trimIndent()
+        assertNull(UpdateChecker.pickUpdate(json, "1.0.0"))
+    }
+
+    @Test
+    fun `pickUpdate skips a release with no matching apk asset`() {
+        val json = """
+            [
+              { "tag_name": "v1.1.0", "draft": false, "prerelease": false,
+                "assets": [ { "name": "checksums.txt" } ] }
+            ]
+        """.trimIndent()
+        assertNull(UpdateChecker.pickUpdate(json, "1.0.0"))
+    }
+
+    @Test
+    fun `pickUpdate returns null for malformed json`() {
+        assertNull(UpdateChecker.pickUpdate("not json", "1.0.0"))
+    }
+
+    @Test
+    fun `pickUpdate returns null when currentVersion itself is malformed`() {
+        val json = """
+            [
+              { "tag_name": "v1.1.0", "draft": false, "prerelease": false,
+                "assets": [ { "name": "KwabaTV.apk" } ] }
+            ]
+        """.trimIndent()
+        assertNull(UpdateChecker.pickUpdate(json, "not-a-version"))
+    }
+
+    @Test
+    fun `pickUpdate picks the highest of multiple qualifying releases`() {
+        val json = """
+            [
+              { "tag_name": "v1.1.0", "draft": false, "prerelease": false,
+                "assets": [ { "name": "KwabaTV.apk" } ] },
+              { "tag_name": "v1.2.0", "draft": false, "prerelease": false,
+                "assets": [ { "name": "KwabaTV.apk" } ] }
+            ]
+        """.trimIndent()
+        val result = UpdateChecker.pickUpdate(json, "1.0.0")
+        assertEquals("1.2.0", result?.version)
+    }
+}
+```
+
+- [ ] **Step 4: Run the tests and verify they fail**
+
+Run: `cd /c/Projekte/kwabatv && JAVA_HOME="/c/Users/GGB/jdks/jdk-21.0.12.1+1" ./gradlew.bat testDebugUnitTest --tests "de.ggb.kwabatv.UpdateCheckerTest"`
+
+Expected: build reaches the test task and reports FAILED, with most of the 13 tests failing (the stubs return `null`/`0` unconditionally, so any test expecting a real value fails). This confirms the tests actually exercise `UpdateChecker` rather than trivially passing.
+
+- [ ] **Step 5: Replace the stub with the real implementation**
+
+Replace the full contents of `app/src/main/java/de/ggb/kwabatv/UpdateChecker.kt` with:
+
+```kotlin
+package de.ggb.kwabatv
+
+import org.json.JSONArray
+
+/** A qualifying update found on Gitea: display version and the APK's direct download URL. */
+data class UpdateInfo(val version: String, val apkDownloadUrl: String)
+
+/**
+ * Checks the public KwabaTV Gitea repo for a newer release. Fully self-contained - no
+ * kwaba-sync server involvement, since GGB/KwabaTV is a public repo and its releases API
+ * needs no authentication. See docs/superpowers/specs/2026-09-27-in-app-updates-design.md.
+ */
+object UpdateChecker {
+    private const val RELEASES_API_URL = "https://git.whodovoodoo.de/api/v1/repos/GGB/KwabaTV/releases"
+    private const val DOWNLOAD_BASE_URL = "https://git.whodovoodoo.de/GGB/KwabaTV/releases/download"
+    private const val ASSET_NAME = "KwabaTV.apk"
+    private val VERSION_RE = Regex("""^(\d+)\.(\d+)\.(\d+)$""")
+
+    /** Parses a bare "X.Y.Z" version string (no "v" prefix) into [major, minor, patch], or null if malformed. */
+    fun parseVersion(version: String): List<Int>? {
+        val m = VERSION_RE.matchEntire(version) ?: return null
+        return m.groupValues.drop(1).map { it.toInt() }
+    }
+
+    /** Positive if [a] is newer than [b], negative if older, 0 if equal. Both must be 3-element lists. */
+    fun compareVersions(a: List<Int>, b: List<Int>): Int {
+        for (i in 0..2) {
+            val diff = a[i] - b[i]
+            if (diff != 0) return diff
+        }
+        return 0
+    }
+
+    /**
+     * Picks the newest qualifying release from a Gitea releases API JSON array: not a draft,
+     * not a prerelease, tag matches "vX.Y.Z", newer than [currentVersion], and has a
+     * "KwabaTV.apk" asset. Returns null if none qualify or the JSON is malformed. The download
+     * URL is built manually from tag + asset name (same approach as kwaba-sync's own
+     * src/desktop-release.js) rather than trusting the API response's browser_download_url.
+     */
+    fun pickUpdate(releasesJson: String, currentVersion: String): UpdateInfo? {
+        val current = parseVersion(currentVersion) ?: return null
+        val releases = try { JSONArray(releasesJson) } catch (e: Exception) { return null }
+
+        var best: Pair<List<Int>, UpdateInfo>? = null
+        for (i in 0 until releases.length()) {
+            val release = releases.optJSONObject(i) ?: continue
+            if (release.optBoolean("draft", false) || release.optBoolean("prerelease", false)) continue
+
+            val tag = release.optString("tag_name", "")
+            if (!tag.startsWith("v")) continue
+            val version = parseVersion(tag.substring(1)) ?: continue
+            if (compareVersions(version, current) <= 0) continue
+
+            val assets = release.optJSONArray("assets") ?: continue
+            var hasApk = false
+            for (j in 0 until assets.length()) {
+                if (assets.optJSONObject(j)?.optString("name") == ASSET_NAME) { hasApk = true; break }
+            }
+            if (!hasApk) continue
+
+            if (best == null || compareVersions(version, best!!.first) > 0) {
+                best = version to UpdateInfo(version.joinToString("."), "$DOWNLOAD_BASE_URL/$tag/$ASSET_NAME")
+            }
+        }
+        return best?.second
+    }
+}
+```
+
+- [ ] **Step 6: Run the tests and verify they pass**
+
+Run: `cd /c/Projekte/kwabatv && JAVA_HOME="/c/Users/GGB/jdks/jdk-21.0.12.1+1" ./gradlew.bat testDebugUnitTest --tests "de.ggb.kwabatv.UpdateCheckerTest"`
+
+Expected: BUILD SUCCESSFUL, all 13 tests pass.
+
+- [ ] **Step 7: Commit**
+
+```bash
+cd /c/Projekte/kwabatv
+git add app/build.gradle.kts app/src/main/java/de/ggb/kwabatv/UpdateChecker.kt app/src/test/java/de/ggb/kwabatv/UpdateCheckerTest.kt
+git commit -m "Add unit-tested update-version comparison logic"
+```
+
+---
+
+### Task 2: Real network fetch + version bump
+
+**Files:**
+- Modify: `app/src/main/java/de/ggb/kwabatv/UpdateChecker.kt` (append one function to the `object UpdateChecker` from Task 1)
+- Modify: `app/build.gradle.kts:14-15` (version bump)
+
+**Interfaces:**
+- Consumes: `UpdateChecker.pickUpdate(releasesJson: String, currentVersion: String): UpdateInfo?` (Task 1).
+- Produces: `UpdateChecker.checkForUpdate(currentVersion: String): UpdateInfo?` — does a real network call, returns null on any failure. Task 3's `MainActivity` calls this directly.
+
+- [ ] **Step 1: Confirm the real Gitea API response shape matches what `pickUpdate` expects**
+
+Run: `curl -s "https://git.whodovoodoo.de/api/v1/repos/GGB/KwabaTV/releases" | head -c 1000`
+
+Expected: a JSON array (possibly empty, `[]`, if no releases are published yet — that's fine, it just means `checkForUpdate` will correctly return null against real data). If any releases exist, confirm each object has `tag_name`, `draft`, `prerelease`, and `assets` (an array of objects with `name`) — these are the exact fields `pickUpdate` reads. No code changes in this step, just verification against the live API before wiring up the caller.
+
+- [ ] **Step 2: Add `checkForUpdate` to `UpdateChecker.kt`**
+
+Add these imports to the top of `app/src/main/java/de/ggb/kwabatv/UpdateChecker.kt` (after `import org.json.JSONArray`):
+
+```kotlin
+import java.net.HttpURLConnection
+import java.net.URL
+```
+
+Add this function inside `object UpdateChecker { ... }`, after `pickUpdate`:
+
+```kotlin
+    /**
+     * Fetches the releases list and returns the newest qualifying update, or null - including
+     * on any failure (network unreachable, non-200 response, malformed body). An update check
+     * is a nice-to-have; it must never be able to crash or visibly disrupt normal app use.
+     */
+    fun checkForUpdate(currentVersion: String): UpdateInfo? {
+        return try {
+            val connection = URL(RELEASES_API_URL).openConnection() as HttpURLConnection
+            connection.connectTimeout = 8000
+            connection.readTimeout = 8000
+            connection.requestMethod = "GET"
+            connection.setRequestProperty("Accept", "application/json")
+            if (connection.responseCode != 200) return null
+            val body = connection.inputStream.bufferedReader().use { it.readText() }
+            pickUpdate(body, currentVersion)
+        } catch (e: Exception) {
+            null
+        }
+    }
+```
+
+- [ ] **Step 3: Bump the app version**
+
+In `app/build.gradle.kts`, current lines 14-15:
+
+```kotlin
+        versionCode = 1
+        versionName = "1.0"
+```
+
+Replace with:
+
+```kotlin
+        versionCode = 2
+        versionName = "1.1.0"
+```
+
+- [ ] **Step 4: Verify the project still builds**
+
+Run: `cd /c/Projekte/kwabatv && JAVA_HOME="/c/Users/GGB/jdks/jdk-21.0.12.1+1" ./gradlew.bat assembleDebug`
+
+Expected: BUILD SUCCESSFUL. This confirms `checkForUpdate` compiles correctly against the real `HttpURLConnection`/`URL` APIs — it isn't unit-tested (real network I/O), so this compile check plus Task 3's real-device test are its verification.
+
+- [ ] **Step 5: Commit**
+
+```bash
+cd /c/Projekte/kwabatv
+git add app/src/main/java/de/ggb/kwabatv/UpdateChecker.kt app/build.gradle.kts
+git commit -m "Add real Gitea release fetch; bump version to 1.1.0"
+```
+
+---
+
+### Task 3: Wire into MainActivity — dialog, permission gate, download, install
+
+**Files:**
+- Modify: `app/src/main/AndroidManifest.xml:4` (new permission)
+- Modify: `app/src/main/java/de/ggb/kwabatv/MainActivity.kt` (imports, new fields, `onCreate`/`onDestroy` changes, new private methods)
+
+**Interfaces:**
+- Consumes: `UpdateChecker.checkForUpdate(currentVersion: String): UpdateInfo?` (Task 2), `UpdateInfo(version: String, apkDownloadUrl: String)` (Task 1).
+
+- [ ] **Step 1: Add the install-packages permission**
+
+In `app/src/main/AndroidManifest.xml`, current line 4:
+
+```xml
+    <uses-permission android:name="android.permission.INTERNET" />
+```
+
+Add directly after it:
+
+```xml
+    <uses-permission android:name="android.permission.INTERNET" />
+    <uses-permission android:name="android.permission.REQUEST_INSTALL_PACKAGES" />
+```
+
+- [ ] **Step 2: Add new imports to `MainActivity.kt`**
+
+Current imports:
+
+```kotlin
+import android.app.Activity
+import android.net.Uri
+import android.os.Bundle
+import android.os.SystemClock
+import android.view.KeyEvent
+import android.view.View
+import android.webkit.PermissionRequest
+import android.webkit.WebChromeClient
+import android.webkit.WebView
+import android.webkit.WebViewClient
+```
+
+Replace with:
+
+```kotlin
+import android.app.Activity
+import android.app.AlertDialog
+import android.app.DownloadManager
+import android.content.BroadcastReceiver
+import android.content.Context
+import android.content.Intent
+import android.content.IntentFilter
+import android.net.Uri
+import android.os.Build
+import android.os.Bundle
+import android.os.SystemClock
+import android.provider.Settings
+import android.view.KeyEvent
+import android.view.View
+import android.webkit.PermissionRequest
+import android.webkit.WebChromeClient
+import android.webkit.WebView
+import android.webkit.WebViewClient
+```
+
+- [ ] **Step 3: Add new fields**
+
+Current field declarations:
+
+```kotlin
+    private lateinit var webView: WebView
+    private var fullscreenView: View? = null
+    private var currentPath: String = "/tv"
+    private var lastThrottledSeekAt = 0L
+```
+
+Replace with:
+
+```kotlin
+    private lateinit var webView: WebView
+    private var fullscreenView: View? = null
+    private var currentPath: String = "/tv"
+    private var lastThrottledSeekAt = 0L
+    private var pendingDownloadId: Long = -1
+    private var receiverRegistered = false
+```
+
+- [ ] **Step 4: Trigger the update check from `onCreate`**
+
+Current end of `onCreate`:
+
+```kotlin
+        webView.loadUrl(BuildConfig.WEBSITE_URL)
+    }
+```
+
+Replace with:
+
+```kotlin
+        webView.loadUrl(BuildConfig.WEBSITE_URL)
+        checkForUpdateInBackground()
+    }
+```
+
+- [ ] **Step 5: Clean up the download receiver in `onDestroy`**
+
+Current:
+
+```kotlin
+    override fun onDestroy() {
+        webView.destroy()
+        super.onDestroy()
+    }
+```
+
+Replace with:
+
+```kotlin
+    override fun onDestroy() {
+        webView.destroy()
+        if (receiverRegistered) { unregisterReceiver(downloadReceiver); receiverRegistered = false }
+        super.onDestroy()
+    }
+```
+
+- [ ] **Step 6: Add the update flow methods**
+
+Add this block right after `onDestroy()` (before `private fun isRoomList()...`):
+
+```kotlin
+    /* ---------------------------------------------------------- In-App-Update
+       Prueft bei jedem Start das oeffentliche KwabaTV-Gitea-Repo auf ein neueres
+       Release (siehe UpdateChecker.kt) und bietet es ueber Androids eigenen
+       Paket-Installer an - nie ohne Bestaetigung, das Betriebssystem selbst
+       erlaubt keine stille Installation. Ein fehlgeschlagener Check ist immer
+       lautlos: kein Fehlerdialog, einfach beim naechsten Start erneut versuchen. */
+
+    private fun checkForUpdateInBackground() {
+        Thread {
+            val update = UpdateChecker.checkForUpdate(BuildConfig.VERSION_NAME)
+            if (update != null) runOnUiThread { showUpdateDialog(update) }
+        }.start()
+    }
+
+    private fun showUpdateDialog(update: UpdateInfo) {
+        AlertDialog.Builder(this)
+            .setTitle("Update verfügbar")
+            .setMessage("KwabaTV v${update.version} ist verfügbar.")
+            .setPositiveButton("Aktualisieren") { _, _ -> startUpdate(update) }
+            .setNegativeButton("Später", null)
+            .show()
+    }
+
+    /* "Unbekannte Apps installieren" ist fuer neue Apps ab Android 8 (API 26)
+       pro App einzeln zu erlauben - ohne das wuerde der Installations-Intent
+       unten stillschweigend nichts tun. Statt automatisch nach der Rueckkehr
+       aus den Einstellungen weiterzumachen (mehr Zustand, mehr Fehlerquellen),
+       muss der Nutzer "Aktualisieren" nach dem Erlauben schlicht erneut
+       druecken - siehe Design-Spec. */
+    private fun startUpdate(update: UpdateInfo) {
+        val canInstall = Build.VERSION.SDK_INT < Build.VERSION_CODES.O || packageManager.canRequestPackageInstalls()
+        if (!canInstall) {
+            startActivity(Intent(Settings.ACTION_MANAGE_UNKNOWN_APP_SOURCES, Uri.parse("package:$packageName")))
+            return
+        }
+        downloadApk(update.apkDownloadUrl)
+    }
+
+    private fun downloadApk(url: String) {
+        val request = DownloadManager.Request(Uri.parse(url))
+            .setTitle("KwabaTV Update")
+            .setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED)
+            .setDestinationInExternalFilesDir(this, null, "KwabaTV-update.apk")
+        val downloadManager = getSystemService(DOWNLOAD_SERVICE) as DownloadManager
+        pendingDownloadId = downloadManager.enqueue(request)
+        // Ab Android 13 (API 33) muss jeder dynamisch registrierte Receiver
+        // explizit als (nicht-)exportiert markiert sein, sonst wirft
+        // registerReceiver() eine SecurityException.
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU) {
+            registerReceiver(downloadReceiver, IntentFilter(DownloadManager.ACTION_DOWNLOAD_COMPLETE), Context.RECEIVER_NOT_EXPORTED)
+        } else {
+            @Suppress("UnspecifiedRegisterReceiverFlag")
+            registerReceiver(downloadReceiver, IntentFilter(DownloadManager.ACTION_DOWNLOAD_COMPLETE))
+        }
+        receiverRegistered = true
+    }
+
+    private val downloadReceiver = object : BroadcastReceiver() {
+        override fun onReceive(context: Context, intent: Intent) {
+            if (intent.getLongExtra(DownloadManager.EXTRA_DOWNLOAD_ID, -1) != pendingDownloadId) return
+            if (receiverRegistered) { unregisterReceiver(this); receiverRegistered = false }
+            val downloadManager = getSystemService(DOWNLOAD_SERVICE) as DownloadManager
+            // getUriForDownloadedFile() returns null for a failed download - that failure is
+            // silent for now too, matching the update check's own error handling (see spec).
+            val uri = downloadManager.getUriForDownloadedFile(pendingDownloadId) ?: return
+            installApk(uri)
+        }
+    }
+
+    private fun installApk(uri: Uri) {
+        val intent = Intent(Intent.ACTION_VIEW).apply {
+            setDataAndType(uri, "application/vnd.android.package-archive")
+            addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
+        }
+        startActivity(intent)
+    }
+
+```
+
+- [ ] **Step 7: Verify the project builds**
+
+Run: `cd /c/Projekte/kwabatv && JAVA_HOME="/c/Users/GGB/jdks/jdk-21.0.12.1+1" ./gradlew.bat assembleDebug`
+
+Expected: BUILD SUCCESSFUL.
+
+- [ ] **Step 8: Commit**
+
+```bash
+cd /c/Projekte/kwabatv
+git add app/src/main/AndroidManifest.xml app/src/main/java/de/ggb/kwabatv/MainActivity.kt
+git commit -m "Wire update check into MainActivity: dialog, download, install"
+```
+
+- [ ] **Step 9: Publish a real test release on the KwabaTV Gitea repo**
+
+This step requires the current `app-debug.apk` (built in Step 7) to be renamed `KwabaTV.apk` and attached to a real Gitea release tagged one version below what's about to be tested, so the *installed* app is older than the *published* release and the update check has something real to find.
+
+- Install the just-built APK (still `versionName "1.1.0"`) normally first via `adb install -r`, confirm it runs.
+- Temporarily edit `app/build.gradle.kts` to `versionName = "1.0.0"` (simulating "an older version is installed"), rebuild (`assembleDebug`), install that older-numbered build via `adb install -r` so the device's installed version is genuinely older than the release you're about to publish.
+- Revert `app/build.gradle.kts` back to `versionName = "1.1.0"` (do not commit the temporary `1.0.0` edit).
+- Rebuild (`assembleDebug`), rename the resulting APK to `KwabaTV.apk`, and publish it as a Gitea release on `GGB/KwabaTV` tagged `v1.1.0` (via the Gitea web UI: Releases → New Release → tag `v1.1.0`, attach `KwabaTV.apk`, publish — not a draft, not a prerelease).
+
+- [ ] **Step 10: Verify the full flow on the real Fire TV Stick**
+
+- Relaunch the app on-device (already showing `1.0.0` per the previous step). Confirm the `AlertDialog` appears: "KwabaTV v1.1.0 ist verfügbar."
+- Press "Aktualisieren". First time through, expect Android to redirect to the "install unknown apps" settings screen for KwabaTV (unless already granted from earlier sideloading in this project) — grant it, return to the app, press "Aktualisieren" again.
+- Confirm `DownloadManager`'s notification shows the download progressing, then Android's own package installer screen appears automatically once it completes.
+- Tap "Install" in the system installer. Confirm the app updates in place and relaunches showing `versionName 1.1.0`.
+- Relaunch the app once more with no newer release published: confirm no dialog appears (already current).
+
+---
+
+## Self-Review Notes
+
+- **Spec coverage:** release convention (Task 1/2), version bump (Task 2), background check on launch (Task 3 Step 4), native `AlertDialog` with DPAD-navigable buttons (Task 3, uses Android's default focusable dialog buttons — no custom styling needed), `DownloadManager`-based download avoiding AndroidX (Task 3), permission gate + `ACTION_MANAGE_UNKNOWN_APP_SOURCES` redirect (Task 3), silent error handling throughout (Task 1-2's `checkForUpdate`/`pickUpdate`, Task 3's receiver), real-device end-to-end verification (Task 3 Steps 9-10). All covered.
+- **Placeholder scan:** none found — every step has complete, concrete code or an exact command.
+- **Type consistency:** `UpdateInfo(version, apkDownloadUrl)` used identically in Task 1 (definition + tests), Task 2 (`checkForUpdate` return type), Task 3 (`showUpdateDialog`/`startUpdate` parameter). `UpdateChecker.checkForUpdate(currentVersion: String): UpdateInfo?` signature matches between Task 2's definition and Task 3's call site (`UpdateChecker.checkForUpdate(BuildConfig.VERSION_NAME)`).

docs/superpowers/specs/2026-09-27-in-app-updates-design.md

@@ -0,0 +1,158 @@
+# In-App Updates — Design
+
+Date: 2026-09-27
+Status: approved, pending implementation plan
+
+## Background
+
+KwabaTV has no update mechanism today — every new build requires a manual
+`adb install -r` sideload from a development machine. That's fine for this
+session's iteration pace, but not sustainable once the app is "done" and
+just sitting on a Fire TV Stick: any future fix requires physically
+reconnecting ADB.
+
+Kwaba Sync's own desktop Electron app (`desktop/`, in the `kwaba-sync`
+repo) already solved an equivalent problem: the server proxies the latest
+GitHub-style release from Gitea (`src/desktop-release.js`), gated behind a
+login because that repository is private, and the Electron app polls it,
+shows an in-window update banner, and never installs without an explicit
+click.
+
+KwabaTV's own Gitea repo (`GGB/KwabaTV`) is public — confirmed via its
+Gitea API (`visibility":"public"`, releases endpoint returns 200
+unauthenticated). That removes the reason the desktop app's design needed a
+server-side proxy at all (private-repo auth). This design is intentionally
+simpler than desktop's as a result: no `kwaba-sync` involvement, no
+server-side changes, no coordination needed with that repo's owner. It
+mirrors desktop's *behavior* (check on launch, never install silently,
+graceful failure) without mirroring its *architecture*.
+
+## Goal
+
+The app checks Gitea for a newer release on every launch, and — if one
+exists — offers to download and install it, entirely on-device.
+
+## Release convention
+
+- `versionName` in `app/build.gradle.kts` moves from the current `"1.0"`
+  to a proper 3-part semver (e.g. `"1.1.0"`) as part of this work, since
+  the comparison logic below assumes major/minor/patch on both sides.
+- Tag format: `vX.Y.Z` (e.g. `v1.1.0`), matching `versionName`.
+- Exactly one APK asset per release, always named `KwabaTV.apk`, so the
+  app never has to guess which asset to download.
+- Releases are published manually for now (no CI in this repo yet).
+  Drafts and pre-releases are ignored by the version check.
+
+## Components
+
+All new code lives in kwabatv; nothing else changes outside it.
+
+**`UpdateChecker.kt`** — a small, self-contained class with one entry
+point, e.g. `checkForUpdate(context, onAvailable: (UpdateInfo) -> Unit)`.
+On a background thread, it does a plain HTTP GET to
+`https://git.whodovoodoo.de/api/v1/repos/GGB/KwabaTV/releases`, picks the
+highest-versioned non-draft, non-prerelease release whose tag matches
+`vX.Y.Z`, and compares it numerically (major/minor/patch) against
+`BuildConfig.VERSION_NAME`. If the release is newer, it calls back with
+`{ version, apkDownloadUrl }` on the main thread. Any failure along the
+way (network unreachable, non-200, malformed JSON, no matching release) is
+swallowed silently — no error UI, no retry logic beyond "try again next
+launch."
+
+**`MainActivity.onCreate()`** calls `UpdateChecker.checkForUpdate(...)`
+right after `webView.loadUrl(BuildConfig.WEBSITE_URL)`, so the check never
+delays getting to content. If the callback fires, it shows a native
+`AlertDialog`:
+
+> **KwabaTV v1.1.0 ist verfügbar**
+> [Aktualisieren]  [Später]
+
+Android's default dialog buttons are focusable and DPAD-navigable with no
+extra work. "Später" just dismisses; the same check runs again next
+launch, with no persisted "skip this version" state.
+
+**Download + install**, triggered by "Aktualisieren":
+
+- Uses `android.app.DownloadManager` (a base-SDK system service — no
+  AndroidX needed, keeping the app's existing zero-dependency footprint)
+  to download the APK asset directly from Gitea's public release URL.
+- Registers a `BroadcastReceiver` for
+  `DownloadManager.ACTION_DOWNLOAD_COMPLETE` to know when the download
+  finishes.
+- On completion, calls `DownloadManager.getUriForDownloadedFile(id)` — this
+  returns a ready-to-use `content://` URI with no custom `FileProvider`
+  setup required (the earlier draft of this design needed one, which
+  would have pulled in an AndroidX dependency; `DownloadManager` avoids
+  that entirely).
+- Fires `Intent(ACTION_VIEW)` with that URI, MIME type
+  `application/vnd.android.package-archive`, and
+  `FLAG_GRANT_READ_URI_PERMISSION`, which opens Android's own system
+  package installer. The user taps "Install" themselves inside that
+  system UI — Android does not allow silent unattended installs, by OS
+  design, regardless of permissions granted.
+
+**First-run permission gate:** before firing the install intent, check
+`packageManager.canRequestPackageInstalls()`. If false (first time ever
+installing an update), send the user to
+`Settings.ACTION_MANAGE_UNKNOWN_APP_SOURCES` for this package instead, so
+they can grant "install unknown apps" for KwabaTV specifically. They then
+press "Aktualisieren" again to retry.
+
+**New manifest entries:**
+- `<uses-permission android:name="android.permission.REQUEST_INSTALL_PACKAGES" />`
+- No new `<provider>` entry (avoided by using `DownloadManager`, see
+  above).
+
+## Data flow
+
+```
+App launch
+  → webView.loadUrl(WEBSITE_URL)          [not blocked by the check]
+  → UpdateChecker (background thread)
+      GET git.whodovoodoo.de/.../releases
+      → newer release found?
+          no  → nothing happens
+          yes → AlertDialog on main thread
+                  "Später"       → nothing further this launch
+                  "Aktualisieren" → canRequestPackageInstalls()?
+                                      no  → Settings.ACTION_MANAGE_UNKNOWN_APP_SOURCES
+                                      yes → DownloadManager.enqueue(apk)
+                                             → ACTION_DOWNLOAD_COMPLETE
+                                             → ACTION_VIEW install intent
+                                             → system installer UI (user taps Install)
+```
+
+## Error handling
+
+Every failure mode in the check itself (DNS/network failure, non-200,
+malformed JSON, no releases, no tag matching `vX.Y.Z`) results in no
+dialog and no visible change — identical to a launch where the app is
+already current. This matches desktop's graceful-degradation philosophy:
+an update check is a nice-to-have, never something that should be able to
+block or degrade normal app use.
+
+Download failures (`DownloadManager` reports a failed status) are also
+silent for now — the user can just press "Aktualisieren" again next
+launch, or manually sideload as a fallback (this doesn't remove that
+option). A visible failure toast is a reasonable future improvement, not
+required for the first version of this feature.
+
+## Testing
+
+This feature cannot be meaningfully unit-tested in isolation — the
+interesting behavior is entirely about real network calls, real Android
+permission state, and the real system package installer. It will be
+verified end-to-end on the real Fire TV Stick used throughout this
+project: publish an actual test release on the `GGB/KwabaTV` Gitea repo,
+then run the full check → dialog → download → permission-gate →
+install flow on-device, the same hands-on verification approach used for
+every other feature this session.
+
+## Out of scope (for this pass)
+
+- Any `kwaba-sync` server changes (Option B from the design discussion —
+  hosting the APK for discovery from the Kwaba website's lobby — is a
+  separate, later concern, not required for in-app updates to work).
+- CI/automated release publishing.
+- Periodic re-checks while the app stays open (check is launch-only).
+- "Skip this version" / persisted dismissal state.