diff --git a/app/src/androidTest/java/org/mozilla/tryfox/data/FakeUserDataRepository.kt b/app/src/androidTest/java/org/mozilla/tryfox/data/FakeUserDataRepository.kt
index 35f29a9..74ee0d8 100644
--- a/app/src/androidTest/java/org/mozilla/tryfox/data/FakeUserDataRepository.kt
+++ b/app/src/androidTest/java/org/mozilla/tryfox/data/FakeUserDataRepository.kt
@@ -8,6 +8,7 @@ import org.mozilla.tryfox.data.SearchHistoryQueryType
 import org.mozilla.tryfox.data.repositories.UserDataRepository
 import org.mozilla.tryfox.lan.LanReceiveIdentity
 import org.mozilla.tryfox.model.HomeScreenLayout
+import org.mozilla.tryfox.util.DEFAULT_PREFERRED_ABI
 
 /**
  * A fake implementation of [org.mozilla.tryfox.data.repositories.UserDataRepository] for testing purposes.
@@ -22,6 +23,8 @@ class FakeUserDataRepository : UserDataRepository {
     override val lanReceiveIdentityFlow: Flow<LanReceiveIdentity?> = _lanReceiveIdentityFlow
     private val _homeScreenLayoutFlow = MutableStateFlow(HomeScreenLayout.OneCardPerApp)
     override val homeScreenLayoutFlow: Flow<HomeScreenLayout> = _homeScreenLayoutFlow
+    private val _preferredAbiFlow = MutableStateFlow(DEFAULT_PREFERRED_ABI)
+    override val preferredAbiFlow: Flow<String> = _preferredAbiFlow
 
     override suspend fun saveLastSearchedEmail(email: String) {
         recordSearch("try", email)
@@ -44,6 +47,10 @@ class FakeUserDataRepository : UserDataRepository {
         _homeScreenLayoutFlow.value = layout
     }
 
+    override suspend fun savePreferredAbi(abiName: String) {
+        _preferredAbiFlow.value = abiName
+    }
+
     // Helper method for tests to clear the stored email if needed
     fun clearLastSearchedEmail() {
         _lastSearchedEmailFlow.value = ""
diff --git a/app/src/main/java/org/mozilla/tryfox/data/DefaultMozillaPackageManager.kt b/app/src/main/java/org/mozilla/tryfox/data/DefaultMozillaPackageManager.kt
index 0a86507..73af1c0 100644
--- a/app/src/main/java/org/mozilla/tryfox/data/DefaultMozillaPackageManager.kt
+++ b/app/src/main/java/org/mozilla/tryfox/data/DefaultMozillaPackageManager.kt
@@ -34,6 +34,7 @@ import org.mozilla.tryfox.util.REFERENCE_BROWSER
 import org.mozilla.tryfox.util.REFERENCE_BROWSER_PACKAGE
 import org.mozilla.tryfox.util.TRYFOX
 import org.mozilla.tryfox.util.TRYFOX_PACKAGE
+import org.mozilla.tryfox.util.abiFromNativeLibraryDir
 
 class DefaultMozillaPackageManager(private val context: Context) : MozillaPackageManager {
 
@@ -61,6 +62,7 @@ class DefaultMozillaPackageManager(private val context: Context) : MozillaPackag
             versionCode = packageInfo?.let { PackageInfoCompat.getLongVersionCode(it) },
             installDateMillis = packageInfo?.lastUpdateTime,
             installingPackageName = if (packageInfo != null) getInstallingPackageName(packageName) else null,
+            activeAbi = abiFromNativeLibraryDir(packageInfo?.applicationInfo?.nativeLibraryDir),
             splitNames = packageInfo?.applicationInfo?.splitNames?.toList() ?: emptyList(),
         )
     }
diff --git a/app/src/main/java/org/mozilla/tryfox/data/repositories/DefaultUserDataRepository.kt b/app/src/main/java/org/mozilla/tryfox/data/repositories/DefaultUserDataRepository.kt
index a8329fd..7d51d3d 100644
--- a/app/src/main/java/org/mozilla/tryfox/data/repositories/DefaultUserDataRepository.kt
+++ b/app/src/main/java/org/mozilla/tryfox/data/repositories/DefaultUserDataRepository.kt
@@ -16,6 +16,7 @@ import org.mozilla.tryfox.data.SearchHistoryEntry
 import org.mozilla.tryfox.data.SearchHistoryQueryType
 import org.mozilla.tryfox.lan.LanReceiveIdentity
 import org.mozilla.tryfox.model.HomeScreenLayout
+import org.mozilla.tryfox.util.DEFAULT_PREFERRED_ABI
 
 /**
  * A repository that stores the last searched email in a DataStore.
@@ -31,6 +32,7 @@ class DefaultUserDataRepository(private val appContext: Context) : UserDataRepos
         val LAN_DEVICE_NAME = stringPreferencesKey("lan_device_name")
         val LAN_SHARED_SECRET = stringPreferencesKey("lan_shared_secret")
         val HOME_SCREEN_LAYOUT = stringPreferencesKey("home_screen_layout")
+        val PREFERRED_ABI = stringPreferencesKey("preferred_abi")
     }
 
     override val searchHistoryFlow: Flow<List<SearchHistoryEntry>> = appContext.dataStore.data.map { preferences ->
@@ -66,6 +68,10 @@ class DefaultUserDataRepository(private val appContext: Context) : UserDataRepos
         homeScreenLayoutFromStoredValue(preferences[PreferenceKeys.HOME_SCREEN_LAYOUT])
     }
 
+    override val preferredAbiFlow: Flow<String> = appContext.dataStore.data.map { preferences ->
+        preferences[PreferenceKeys.PREFERRED_ABI]?.takeIf { it.isNotBlank() } ?: DEFAULT_PREFERRED_ABI
+    }
+
     override suspend fun saveLastSearchedEmail(email: String) {
         recordSearch(project = "try", query = email)
     }
@@ -102,6 +108,12 @@ class DefaultUserDataRepository(private val appContext: Context) : UserDataRepos
         }
     }
 
+    override suspend fun savePreferredAbi(abiName: String) {
+        appContext.dataStore.edit { preferences ->
+            preferences[PreferenceKeys.PREFERRED_ABI] = abiName
+        }
+    }
+
     private fun decodeSearchHistory(serializedHistory: String): List<SearchHistoryEntry> =
         runCatching { json.decodeFromString<List<SearchHistoryEntry>>(serializedHistory) }.getOrDefault(emptyList())
 
diff --git a/app/src/main/java/org/mozilla/tryfox/data/repositories/UserDataRepository.kt b/app/src/main/java/org/mozilla/tryfox/data/repositories/UserDataRepository.kt
index 4ad6628..5b9c2ba 100644
--- a/app/src/main/java/org/mozilla/tryfox/data/repositories/UserDataRepository.kt
+++ b/app/src/main/java/org/mozilla/tryfox/data/repositories/UserDataRepository.kt
@@ -18,6 +18,9 @@ interface UserDataRepository {
     val lanReceiveIdentityFlow: Flow<LanReceiveIdentity?>
     val homeScreenLayoutFlow: Flow<HomeScreenLayout>
 
+    /** The ABI variant to favour when a build offers several. Emits `universal` by default. */
+    val preferredAbiFlow: Flow<String>
+
     /**
      * Saves the last searched email.
      * @param email The email to save.
@@ -26,4 +29,5 @@ interface UserDataRepository {
     suspend fun recordSearch(project: String, query: String, searchedAt: Long = System.currentTimeMillis())
     suspend fun saveLanReceiveIdentity(identity: LanReceiveIdentity)
     suspend fun saveHomeScreenLayout(layout: HomeScreenLayout)
+    suspend fun savePreferredAbi(abiName: String)
 }
diff --git a/app/src/main/java/org/mozilla/tryfox/model/AppState.kt b/app/src/main/java/org/mozilla/tryfox/model/AppState.kt
index 517aa11..1bbd440 100644
--- a/app/src/main/java/org/mozilla/tryfox/model/AppState.kt
+++ b/app/src/main/java/org/mozilla/tryfox/model/AppState.kt
@@ -11,6 +11,7 @@ data class AppState(
     val installDateMillis: Long?,
     val installingPackageName: String? = null,
     val versionCode: Long? = null,
+    val activeAbi: String? = null,
     val splitNames: List<String> = emptyList(),
 ) {
     val isInstalled: Boolean
diff --git a/app/src/main/java/org/mozilla/tryfox/ui/composables/ArchiveGroupCard.kt b/app/src/main/java/org/mozilla/tryfox/ui/composables/ArchiveGroupCard.kt
index a08061c..fca2bc8 100644
--- a/app/src/main/java/org/mozilla/tryfox/ui/composables/ArchiveGroupCard.kt
+++ b/app/src/main/java/org/mozilla/tryfox/ui/composables/ArchiveGroupCard.kt
@@ -80,6 +80,8 @@ import org.mozilla.tryfox.install.InstallState
 import org.mozilla.tryfox.model.AppState
 import org.mozilla.tryfox.ui.models.ApkUiModel
 import org.mozilla.tryfox.ui.models.NightlyBuildOption
+import org.mozilla.tryfox.ui.models.preferredAbiApk
+import org.mozilla.tryfox.util.DEFAULT_PREFERRED_ABI
 import org.mozilla.tryfox.util.FENIX
 import org.mozilla.tryfox.util.FENIX_BETA
 import org.mozilla.tryfox.util.FENIX_RELEASE
@@ -124,6 +126,7 @@ fun ArchiveGroupCard(
     onDismissBuildPicker: () -> Unit = {},
     installStates: Map<String, InstallState> = emptyMap(),
     onOpenInstalledApp: (String) -> Unit = {},
+    preferredAbi: String = DEFAULT_PREFERRED_ABI,
 ) {
     if (pendingBuildOptions.isNotEmpty()) {
         NightlyBuildPickerDialog(
@@ -200,6 +203,7 @@ fun ArchiveGroupCard(
                         appState,
                         installStates,
                         onOpenInstalledApp,
+                        preferredAbi,
                     )
                 }
 
@@ -623,9 +627,13 @@ private fun ArchiveGroupAbiSelector(
     appState: AppState?,
     installStates: Map<String, InstallState>,
     onOpenInstalledApp: (String) -> Unit,
+    preferredAbi: String,
 ) {
-    val firstSupportedIndex = apks.indexOfFirst { it.abi.isSupported }.takeIf { it != -1 } ?: 0
-    var selectedIndex by remember { mutableStateOf(firstSupportedIndex) }
+    val preferredIndex = apks.preferredAbiApk(preferredAbi)
+        ?.let(apks::indexOf)
+        ?.takeIf { it != -1 }
+        ?: 0
+    var selectedIndex by remember { mutableStateOf(preferredIndex) }
 
     Column(
         horizontalAlignment = Alignment.CenterHorizontally,
diff --git a/app/src/main/java/org/mozilla/tryfox/ui/composables/CurrentInstallState.kt b/app/src/main/java/org/mozilla/tryfox/ui/composables/CurrentInstallState.kt
index 0e1617c..f917871 100644
--- a/app/src/main/java/org/mozilla/tryfox/ui/composables/CurrentInstallState.kt
+++ b/app/src/main/java/org/mozilla/tryfox/ui/composables/CurrentInstallState.kt
@@ -172,6 +172,13 @@ private fun InstallMetadataBottomSheet(
                 label = stringResource(id = R.string.install_metadata_source_label),
                 value = installSourceLabel(appState),
             )
+            InstallMetadataRow(
+                // The ABI Android selected at install time. A universal APK reports the single
+                // architecture the platform kept, so this does not identify the APK variant.
+                label = stringResource(id = R.string.install_metadata_abi_label),
+                value = appState.activeAbi
+                    ?: stringResource(id = R.string.install_metadata_abi_none),
+            )
             InstallMetadataBlock(
                 label = stringResource(id = R.string.install_metadata_splits_label),
                 // splitNames covers only the config splits; the base APK is always present but not
@@ -233,7 +240,7 @@ private fun InstallMetadataBlock(label: String, value: String) {
             text = value,
             style = MaterialTheme.typography.bodySmall,
             fontFamily = FontFamily.Monospace,
-            modifier = Modifier.padding(top = 2.dp),
+            modifier = Modifier.padding(start = 8.dp, top = 2.dp),
         )
     }
 }
diff --git a/app/src/main/java/org/mozilla/tryfox/ui/models/AbiUiModel.kt b/app/src/main/java/org/mozilla/tryfox/ui/models/AbiUiModel.kt
index 8111e33..2e23007 100644
--- a/app/src/main/java/org/mozilla/tryfox/ui/models/AbiUiModel.kt
+++ b/app/src/main/java/org/mozilla/tryfox/ui/models/AbiUiModel.kt
@@ -1,6 +1,21 @@
 package org.mozilla.tryfox.ui.models
 
+import org.mozilla.tryfox.util.isUniversalAbi
+
 data class AbiUiModel(
     val name: String?,
     val isSupported: Boolean,
-)
+) {
+    val isUniversal: Boolean get() = isUniversalAbi(name)
+}
+
+/**
+ * Picks the variant matching [preferredAbi], falling back to universal, then to anything the
+ * device can install, then to whatever came first. Nightly builds ship no universal variant, so
+ * an unmatched affinity still resolves to an installable APK.
+ */
+fun List<ApkUiModel>.preferredAbiApk(preferredAbi: String): ApkUiModel? =
+    firstOrNull { preferredAbi.equals(it.abi.name, ignoreCase = true) }
+        ?: firstOrNull { it.abi.isUniversal }
+        ?: firstOrNull { it.abi.isSupported }
+        ?: firstOrNull()
diff --git a/app/src/main/java/org/mozilla/tryfox/ui/models/AppUiModel.kt b/app/src/main/java/org/mozilla/tryfox/ui/models/AppUiModel.kt
index 5bb2323..339425d 100644
--- a/app/src/main/java/org/mozilla/tryfox/ui/models/AppUiModel.kt
+++ b/app/src/main/java/org/mozilla/tryfox/ui/models/AppUiModel.kt
@@ -27,6 +27,7 @@ data class AppUiModel(
     val installedDate: String?,
     val installingPackageName: String? = null,
     val splitNames: List<String> = emptyList(),
+    val activeAbi: String? = null,
     val installedTryBuild: InstalledTryBuild? = null,
     val apks: ApksResult,
     val userPickedDate: LocalDate? = null,
diff --git a/app/src/main/java/org/mozilla/tryfox/ui/screens/HomeAppCard.kt b/app/src/main/java/org/mozilla/tryfox/ui/screens/HomeAppCard.kt
index 6a7aa7c..fa4ee4e 100644
--- a/app/src/main/java/org/mozilla/tryfox/ui/screens/HomeAppCard.kt
+++ b/app/src/main/java/org/mozilla/tryfox/ui/screens/HomeAppCard.kt
@@ -67,6 +67,8 @@ import org.mozilla.tryfox.ui.models.ApkUiModel
 import org.mozilla.tryfox.ui.models.ApksResult
 import org.mozilla.tryfox.ui.models.AppUiModel
 import org.mozilla.tryfox.ui.models.NightlyBuildOption
+import org.mozilla.tryfox.ui.models.preferredAbiApk
+import org.mozilla.tryfox.util.DEFAULT_PREFERRED_ABI
 import org.mozilla.tryfox.util.FENIX
 import org.mozilla.tryfox.util.FENIX_BETA
 import org.mozilla.tryfox.util.FENIX_DEBUG
@@ -94,6 +96,7 @@ internal fun HomeAppCard(
     onBuildSelected: (String, String) -> Unit,
     onDismissBuildPicker: (String) -> Unit,
     modifier: Modifier = Modifier,
+    preferredAbi: String = DEFAULT_PREFERRED_ABI,
 ) {
     val app = card.selectedApp
     val appState = app.toAppState()
@@ -104,8 +107,7 @@ internal fun HomeAppCard(
     val isNightly = app.name == FENIX || app.name == FOCUS
     val isDebug = app.name == FENIX_DEBUG || app.name == FOCUS_DEBUG
     val isVersionSelectable = app.name in setOf(FENIX_RELEASE, FENIX_BETA, FOCUS_RELEASE, FOCUS_BETA)
-    val selectedApk = (app.apks as? ApksResult.Success)?.apks
-        ?.let { apks -> apks.firstOrNull { it.abi.isSupported } ?: apks.firstOrNull() }
+    val selectedApk = (app.apks as? ApksResult.Success)?.apks?.preferredAbiApk(preferredAbi)
 
     Card(
         modifier = modifier
@@ -340,6 +342,7 @@ private fun AppUiModel.toAppState(): AppState? = installedVersion?.let { version
         installDateMillis = installedDate?.let(::parseDateToMillis),
         installingPackageName = installingPackageName,
         versionCode = installedVersionCode,
+        activeAbi = activeAbi,
         splitNames = splitNames,
     )
 }
diff --git a/app/src/main/java/org/mozilla/tryfox/ui/screens/HomeScreen.kt b/app/src/main/java/org/mozilla/tryfox/ui/screens/HomeScreen.kt
index 09b2ab9..83e9fb8 100644
--- a/app/src/main/java/org/mozilla/tryfox/ui/screens/HomeScreen.kt
+++ b/app/src/main/java/org/mozilla/tryfox/ui/screens/HomeScreen.kt
@@ -221,6 +221,7 @@ fun HomeScreen(
                                 onDismissBuildPicker = { appName ->
                                     homeViewModel.onDismissBuildPicker(appName)
                                 },
+                                preferredAbi = currentScreenState.preferredAbi,
                             )
                         }
                     }
diff --git a/app/src/main/java/org/mozilla/tryfox/ui/screens/HomeScreenState.kt b/app/src/main/java/org/mozilla/tryfox/ui/screens/HomeScreenState.kt
index 58f5668..1beda2f 100644
--- a/app/src/main/java/org/mozilla/tryfox/ui/screens/HomeScreenState.kt
+++ b/app/src/main/java/org/mozilla/tryfox/ui/screens/HomeScreenState.kt
@@ -3,6 +3,7 @@ package org.mozilla.tryfox.ui.screens
 import org.mozilla.tryfox.model.CacheManagementState
 import org.mozilla.tryfox.model.HomeScreenLayout
 import org.mozilla.tryfox.ui.models.AppUiModel
+import org.mozilla.tryfox.util.DEFAULT_PREFERRED_ABI
 
 /**
  * Represents the various states of the Home screen.
@@ -23,5 +24,6 @@ sealed class HomeScreenState {
         val isDownloadingAnyFile: Boolean,
         val selectedAppNames: Map<HomeAppFamily, String> = HomeAppFamily.entries.associateWith { it.defaultAppName },
         val homeScreenLayout: HomeScreenLayout = HomeScreenLayout.OneCardPerApp,
+        val preferredAbi: String = DEFAULT_PREFERRED_ABI,
     ) : HomeScreenState()
 }
diff --git a/app/src/main/java/org/mozilla/tryfox/ui/screens/HomeViewModel.kt b/app/src/main/java/org/mozilla/tryfox/ui/screens/HomeViewModel.kt
index abd3120..11a440f 100644
--- a/app/src/main/java/org/mozilla/tryfox/ui/screens/HomeViewModel.kt
+++ b/app/src/main/java/org/mozilla/tryfox/ui/screens/HomeViewModel.kt
@@ -50,6 +50,7 @@ import org.mozilla.tryfox.ui.models.ApksResult
 import org.mozilla.tryfox.ui.models.AppUiModel
 import org.mozilla.tryfox.ui.models.NightlyBuildOption
 import org.mozilla.tryfox.ui.models.newVersionAvailable
+import org.mozilla.tryfox.util.DEFAULT_PREFERRED_ABI
 import org.mozilla.tryfox.util.FENIX
 import org.mozilla.tryfox.util.FENIX_BETA
 import org.mozilla.tryfox.util.FENIX_DEBUG
@@ -60,6 +61,8 @@ import org.mozilla.tryfox.util.FOCUS_DEBUG
 import org.mozilla.tryfox.util.FOCUS_RELEASE
 import org.mozilla.tryfox.util.REFERENCE_BROWSER
 import org.mozilla.tryfox.util.TRYFOX
+import org.mozilla.tryfox.util.isAbiSupported
+import org.mozilla.tryfox.util.resolvePreferredAbi
 import java.io.File
 
 /**
@@ -100,6 +103,9 @@ class HomeViewModel(
     private var tryFoxCardDismissed = false
     private var homeScreenLayout = HomeScreenLayout.OneCardPerApp
 
+    @Volatile
+    private var preferredAbi = DEFAULT_PREFERRED_ABI
+
     @Volatile
     private var selectedHomeAppNames = HomeAppFamily.entries.associateWith { it.defaultAppName }
     private val appMutationVersions = mutableMapOf<String, Long>()
@@ -139,6 +145,20 @@ class HomeViewModel(
             }
             ?.launchIn(viewModelScope)
 
+        userDataRepository?.preferredAbiFlow
+            ?.onEach { storedAbi ->
+                val resolvedAbi = resolvePreferredAbi(storedAbi, supportedAbis)
+                preferredAbi = resolvedAbi
+                _homeScreenState.update { currentState ->
+                    if (currentState is HomeScreenState.Loaded) {
+                        currentState.copy(preferredAbi = resolvedAbi)
+                    } else {
+                        currentState
+                    }
+                }
+            }
+            ?.launchIn(viewModelScope)
+
         mozillaPackageManager.appStates
             .onEach { appState ->
                 _homeScreenState.update { currentState ->
@@ -151,6 +171,7 @@ class HomeViewModel(
                                         installedVersionCode = appState.versionCode,
                                         installedDate = appState.formattedInstallDate,
                                         installingPackageName = appState.installingPackageName,
+                                        activeAbi = appState.activeAbi,
                                         splitNames = appState.splitNames,
                                         installedTryBuild = app.name.takeIf { it == FENIX_DEBUG }
                                             ?.let { matchingInstalledTryBuild(appState) },
@@ -327,6 +348,7 @@ class HomeViewModel(
         installedDate = appState?.formattedInstallDate,
         installingPackageName = appState?.installingPackageName,
         splitNames = appState?.splitNames ?: emptyList(),
+        activeAbi = appState?.activeAbi,
         installedTryBuild = appState?.takeIf { name == FENIX_DEBUG }
             ?.let { matchingInstalledTryBuild(it) },
     )
@@ -343,6 +365,7 @@ class HomeViewModel(
             isDownloadingAnyFile = false,
             selectedAppNames = selectedHomeAppNames,
             homeScreenLayout = homeScreenLayout,
+            preferredAbi = preferredAbi,
         ).applyDownloadStates(downloadStates.value)
     }
 
@@ -401,6 +424,7 @@ class HomeViewModel(
         installedDate = appState?.formattedInstallDate,
         installingPackageName = appState?.installingPackageName,
         splitNames = appState?.splitNames.orEmpty(),
+        activeAbi = appState?.activeAbi,
         installedTryBuild = appState?.takeIf { appName == FENIX_DEBUG }?.let(::matchingInstalledTryBuild),
         apks = ApksResult.Success(apks.map { it.toUiModel() }),
         selectedReleaseVersion = selectedReleaseVersion,
@@ -476,6 +500,7 @@ class HomeViewModel(
             installedDate = appState?.formattedInstallDate,
             installingPackageName = appState?.installingPackageName,
             splitNames = appState?.splitNames ?: emptyList(),
+            activeAbi = appState?.activeAbi,
             installedTryBuild = appState?.takeIf { repository.appName == FENIX_DEBUG }?.let(::matchingInstalledTryBuild),
             apks = apksResult,
             selectedReleaseVersion = selectedReleaseVersion,
@@ -487,12 +512,8 @@ class HomeViewModel(
         return parsedApks.map { parsedApk ->
             val buildDate = parsedApk.rawDateString?.rawNightlyBuildDate()
             val date = buildDate?.let { parsedApk.rawDateString?.formatNightlyBuildDate().orEmpty() }.orEmpty()
-            val isCompatible = supportedAbis.any { deviceAbi ->
-                deviceAbi.equals(
-                    parsedApk.abiName,
-                    ignoreCase = true,
-                )
-            }
+            // Universal APKs bundle every architecture, so they install anywhere.
+            val isCompatible = isAbiSupported(parsedApk.abiName, supportedAbis)
 
             // Key the cache dir / unique key by the full build timestamp (yyyy-MM-dd-HH-mm-ss) so
             // two Nightly builds from the same day don't collide on a date-only path. Releases have
diff --git a/app/src/main/java/org/mozilla/tryfox/ui/screens/SettingsScreen.kt b/app/src/main/java/org/mozilla/tryfox/ui/screens/SettingsScreen.kt
index cb44e48..0ca37ca 100644
--- a/app/src/main/java/org/mozilla/tryfox/ui/screens/SettingsScreen.kt
+++ b/app/src/main/java/org/mozilla/tryfox/ui/screens/SettingsScreen.kt
@@ -43,6 +43,7 @@ import androidx.compose.runtime.setValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.platform.LocalContext
+import androidx.compose.ui.platform.testTag
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.semantics.Role
 import androidx.compose.ui.semantics.selected
@@ -54,6 +55,7 @@ import org.mozilla.tryfox.data.managers.NotificationManager
 import org.mozilla.tryfox.data.managers.NotificationPermissionState
 import org.mozilla.tryfox.model.CacheManagementState
 import org.mozilla.tryfox.model.HomeScreenLayout
+import org.mozilla.tryfox.util.isUniversalAbi
 
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
@@ -154,6 +156,12 @@ fun SettingsScreen(
                 selectedLayout = uiState.homeScreenLayout,
                 onLayoutSelected = settingsViewModel::selectHomeScreenLayout,
             )
+            HorizontalDivider(modifier = Modifier.padding(horizontal = 16.dp))
+            AbiSettingsCard(
+                selectedAbi = uiState.preferredAbi,
+                abiOptions = uiState.abiOptions,
+                onAbiSelected = settingsViewModel::selectPreferredAbi,
+            )
         }
     }
 }
@@ -260,6 +268,50 @@ private fun HomeLayoutSettingsCard(
     }
 }
 
+@Composable
+private fun AbiSettingsCard(
+    selectedAbi: String,
+    abiOptions: List<String>,
+    onAbiSelected: (String) -> Unit,
+) {
+    Column(verticalArrangement = Arrangement.spacedBy(8.dp)) {
+        SettingsSectionTitle(R.string.settings_abi_section_title)
+        Text(
+            text = stringResource(R.string.settings_abi_description),
+            style = MaterialTheme.typography.bodyMedium,
+            color = MaterialTheme.colorScheme.onSurfaceVariant,
+            modifier = Modifier.padding(horizontal = 16.dp),
+        )
+        PreferenceGroup {
+            abiOptions.forEachIndexed { index, abiName ->
+                if (index > 0) HorizontalDivider(modifier = Modifier.padding(start = 16.dp))
+                val selected = abiName.equals(selectedAbi, ignoreCase = true)
+                ListItem(
+                    headlineContent = {
+                        Text(
+                            if (isUniversalAbi(abiName)) {
+                                stringResource(R.string.settings_abi_universal_label)
+                            } else {
+                                abiName
+                            },
+                        )
+                    },
+                    supportingContent = if (isUniversalAbi(abiName)) {
+                        { Text(stringResource(R.string.settings_abi_universal_description)) }
+                    } else {
+                        null
+                    },
+                    trailingContent = { RadioButton(selected = selected, onClick = null) },
+                    modifier = Modifier
+                        .semantics { this.selected = selected }
+                        .testTag("settings_abi_option_$abiName")
+                        .clickable(role = Role.RadioButton) { onAbiSelected(abiName) },
+                )
+            }
+        }
+    }
+}
+
 @Composable
 private fun PreferenceGroup(content: @Composable ColumnScope.() -> Unit) {
     Card(
diff --git a/app/src/main/java/org/mozilla/tryfox/ui/screens/SettingsViewModel.kt b/app/src/main/java/org/mozilla/tryfox/ui/screens/SettingsViewModel.kt
index bc42da2..df5fb1a 100644
--- a/app/src/main/java/org/mozilla/tryfox/ui/screens/SettingsViewModel.kt
+++ b/app/src/main/java/org/mozilla/tryfox/ui/screens/SettingsViewModel.kt
@@ -1,5 +1,6 @@
 package org.mozilla.tryfox.ui.screens
 
+import android.os.Build
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.viewModelScope
 import kotlinx.coroutines.flow.SharingStarted
@@ -12,12 +13,17 @@ import org.mozilla.tryfox.data.repositories.UserDataRepository
 import org.mozilla.tryfox.download.ApkDownloadCoordinator
 import org.mozilla.tryfox.model.CacheManagementState
 import org.mozilla.tryfox.model.HomeScreenLayout
+import org.mozilla.tryfox.util.DEFAULT_PREFERRED_ABI
+import org.mozilla.tryfox.util.abiPreferenceOptions
+import org.mozilla.tryfox.util.resolvePreferredAbi
 
 data class SettingsUiState(
     val cacheState: CacheManagementState = CacheManagementState.IdleEmpty,
     val cacheSizeBytes: Long = 0L,
     val hasActiveDownloads: Boolean = false,
     val homeScreenLayout: HomeScreenLayout = HomeScreenLayout.OneCardPerApp,
+    val preferredAbi: String = DEFAULT_PREFERRED_ABI,
+    val abiOptions: List<String> = listOf(DEFAULT_PREFERRED_ABI),
 ) {
     val canClearCache: Boolean
         get() = cacheState == CacheManagementState.IdleNonEmpty && !hasActiveDownloads
@@ -27,20 +33,26 @@ class SettingsViewModel(
     private val cacheManager: CacheManager,
     downloadCoordinator: ApkDownloadCoordinator,
     private val userDataRepository: UserDataRepository,
+    supportedAbis: List<String> = runCatching { Build.SUPPORTED_ABIS.toList() }.getOrDefault(emptyList()),
 ) : ViewModel() {
+    private val abiOptions = abiPreferenceOptions(supportedAbis)
+
     val uiState: StateFlow<SettingsUiState> = combine(
         cacheManager.cacheState,
         cacheManager.cacheSizeBytes,
         downloadCoordinator.downloads,
         userDataRepository.homeScreenLayoutFlow,
-    ) { cacheState, cacheSizeBytes, downloads, homeScreenLayout ->
+        userDataRepository.preferredAbiFlow,
+    ) { cacheState, cacheSizeBytes, downloads, homeScreenLayout, preferredAbi ->
         SettingsUiState(
             cacheState = cacheState,
             cacheSizeBytes = cacheSizeBytes,
             hasActiveDownloads = downloads.values.any { !it.isTerminal },
             homeScreenLayout = homeScreenLayout,
+            preferredAbi = resolvePreferredAbi(preferredAbi, supportedAbis),
+            abiOptions = abiOptions,
         )
-    }.stateIn(viewModelScope, SharingStarted.Eagerly, SettingsUiState())
+    }.stateIn(viewModelScope, SharingStarted.Eagerly, SettingsUiState(abiOptions = abiOptions))
 
     init {
         viewModelScope.launch { cacheManager.checkCacheStatus() }
@@ -54,4 +66,9 @@ class SettingsViewModel(
     fun selectHomeScreenLayout(layout: HomeScreenLayout) {
         viewModelScope.launch { userDataRepository.saveHomeScreenLayout(layout) }
     }
+
+    fun selectPreferredAbi(abiName: String) {
+        if (abiName !in abiOptions) return
+        viewModelScope.launch { userDataRepository.savePreferredAbi(abiName) }
+    }
 }
diff --git a/app/src/main/java/org/mozilla/tryfox/util/Abi.kt b/app/src/main/java/org/mozilla/tryfox/util/Abi.kt
new file mode 100644
index 0000000..261d774
--- /dev/null
+++ b/app/src/main/java/org/mozilla/tryfox/util/Abi.kt
@@ -0,0 +1,59 @@
+package org.mozilla.tryfox.util
+
+// Retired with NDK r17; the platform still advertises these so pre-ARMv7 APKs keep working, but
+// nothing is built for them any more, so offering them would only ever fall back to universal.
+private val LEGACY_ABIS = setOf("armeabi", "mips", "mips64")
+
+/** The ABI name the archive uses for the APK that bundles every architecture. */
+const val UNIVERSAL_ABI = "universal"
+
+/** The ABI affinity used until the user picks one: universal installs on any device. */
+const val DEFAULT_PREFERRED_ABI = UNIVERSAL_ABI
+
+fun isUniversalAbi(abiName: String?): Boolean = UNIVERSAL_ABI.equals(abiName, ignoreCase = true)
+
+/** True when an APK built for [abiName] can be installed on a device running [deviceAbis]. */
+fun isAbiSupported(abiName: String?, deviceAbis: List<String>): Boolean =
+    isUniversalAbi(abiName) || deviceAbis.any { it.equals(abiName, ignoreCase = true) }
+
+/**
+ * Determine the active ABI for installed package from `ApplicationInfo.nativeLibraryDir` path.
+ *
+ * This corresponds to what ABI was chosen by package manager when the package was installed. The
+ * package itself may have included multiple ABIs, but installer selected a single one that the
+ * application will execute under.
+ */
+fun abiFromNativeLibraryDir(nativeLibraryDir: String?): String? {
+    // The library names don't always match ABI so patch up the ones we know.
+    val directoryAbis = mapOf(
+        "arm64" to "arm64-v8a",
+        "arm" to "armeabi-v7a",
+        "x86_64" to "x86_64",
+        "x86" to "x86",
+    )
+    return nativeLibraryDir
+        ?.trimEnd('/')
+        ?.substringAfterLast('/')
+        ?.lowercase()
+        // A package with no native code stops at the "lib" root, with no architecture below it.
+        ?.takeIf { it.isNotBlank() && it != "lib" }
+        ?.let { directory -> directoryAbis[directory] ?: directory }
+}
+
+/**
+ * The affinity options offered in Settings: universal first, then every ABI the device runs that
+ * an APK could plausibly be built for.
+ */
+fun abiPreferenceOptions(deviceAbis: List<String>): List<String> {
+    val filteredAbis = deviceAbis
+        .filterNot { isUniversalAbi(it) || it.lowercase() in LEGACY_ABIS }
+        .distinct()
+    return listOf(UNIVERSAL_ABI) + filteredAbis
+}
+
+/** Falls back to universal when the stored ABI is blank or no longer supported by this device. */
+fun resolvePreferredAbi(preferredAbi: String?, deviceAbis: List<String>): String =
+    preferredAbi
+        ?.takeIf { it.isNotBlank() }
+        ?.takeIf { abiPreferenceOptions(deviceAbis).any { option -> option.equals(it, ignoreCase = true) } }
+        ?: DEFAULT_PREFERRED_ABI
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 64fb7c5..603c317 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -39,6 +39,10 @@
     <string name="settings_home_layout_description">Choose how apps are grouped on Home.</string>
     <string name="settings_layout_one_card_per_app">One card per app</string>
     <string name="settings_layout_one_card_per_flavor">One card per flavor of each app</string>
+    <string name="settings_abi_section_title">Preferred ABI</string>
+    <string name="settings_abi_description">Which APK variant to offer when a build ships more than one. Builds without this variant fall back to universal.</string>
+    <string name="settings_abi_universal_label">Universal</string>
+    <string name="settings_abi_universal_description">Every architecture in one APK</string>
     <string name="treeherder_apks_search_artifacts_title">Search builds</string>
     <string name="treeherder_apks_project_label">Project</string>
     <string name="treeherder_apks_revision_label">Email or revision</string>
@@ -135,6 +139,8 @@
     <string name="install_metadata_version_code_label">Version code</string>
     <string name="install_metadata_install_date_label">Installed</string>
     <string name="install_metadata_source_label">Source</string>
+    <string name="install_metadata_abi_label">Active ABI</string>
+    <string name="install_metadata_abi_none">none</string>
     <string name="install_metadata_source_play_store">Google Play Store</string>
     <string name="install_metadata_source_sideloaded">Sideloaded</string>
     <string name="install_metadata_splits_label">Splits</string>
diff --git a/app/src/test/java/org/mozilla/tryfox/data/managers/FakeUserDataRepository.kt b/app/src/test/java/org/mozilla/tryfox/data/managers/FakeUserDataRepository.kt
index cf8e8f3..3897376 100644
--- a/app/src/test/java/org/mozilla/tryfox/data/managers/FakeUserDataRepository.kt
+++ b/app/src/test/java/org/mozilla/tryfox/data/managers/FakeUserDataRepository.kt
@@ -8,6 +8,7 @@ import org.mozilla.tryfox.data.SearchHistoryQueryType
 import org.mozilla.tryfox.data.repositories.UserDataRepository
 import org.mozilla.tryfox.lan.LanReceiveIdentity
 import org.mozilla.tryfox.model.HomeScreenLayout
+import org.mozilla.tryfox.util.DEFAULT_PREFERRED_ABI
 
 /**
  * A fake implementation of [UserDataRepository] for testing purposes.
@@ -22,6 +23,8 @@ class FakeUserDataRepository : UserDataRepository {
     override val lanReceiveIdentityFlow: Flow<LanReceiveIdentity?> = _lanReceiveIdentityFlow
     private val _homeScreenLayoutFlow = MutableStateFlow(HomeScreenLayout.OneCardPerApp)
     override val homeScreenLayoutFlow: Flow<HomeScreenLayout> = _homeScreenLayoutFlow
+    private val _preferredAbiFlow = MutableStateFlow(DEFAULT_PREFERRED_ABI)
+    override val preferredAbiFlow: Flow<String> = _preferredAbiFlow
 
     override suspend fun saveLastSearchedEmail(email: String) {
         recordSearch("try", email)
@@ -44,6 +47,10 @@ class FakeUserDataRepository : UserDataRepository {
         _homeScreenLayoutFlow.value = layout
     }
 
+    override suspend fun savePreferredAbi(abiName: String) {
+        _preferredAbiFlow.value = abiName
+    }
+
     // Helper method for tests to clear the stored email if needed
     fun clearLastSearchedEmail() {
         _lastSearchedEmailFlow.value = ""
diff --git a/app/src/test/java/org/mozilla/tryfox/ui/screens/HomeViewModelTest.kt b/app/src/test/java/org/mozilla/tryfox/ui/screens/HomeViewModelTest.kt
index 45a06a9..9a8db65 100644
--- a/app/src/test/java/org/mozilla/tryfox/ui/screens/HomeViewModelTest.kt
+++ b/app/src/test/java/org/mozilla/tryfox/ui/screens/HomeViewModelTest.kt
@@ -61,6 +61,7 @@ import org.mozilla.tryfox.model.MozillaArchiveApk
 import org.mozilla.tryfox.ui.models.AbiUiModel
 import org.mozilla.tryfox.ui.models.ApkUiModel
 import org.mozilla.tryfox.ui.models.ApksResult
+import org.mozilla.tryfox.ui.models.preferredAbiApk
 import org.mozilla.tryfox.util.FENIX
 import org.mozilla.tryfox.util.FENIX_DEBUG
 import org.mozilla.tryfox.util.FENIX_DEBUG_PACKAGE
@@ -70,6 +71,7 @@ import org.mozilla.tryfox.util.FOCUS
 import org.mozilla.tryfox.util.FOCUS_RELEASE
 import org.mozilla.tryfox.util.REFERENCE_BROWSER
 import org.mozilla.tryfox.util.TRYFOX
+import org.mozilla.tryfox.util.UNIVERSAL_ABI
 import java.io.File
 
 @ExperimentalCoroutinesApi
@@ -231,6 +233,43 @@ class HomeViewModelTest {
         assertEquals(HomeScreenLayout.OneCardPerFlavor, state.homeScreenLayout)
     }
 
+    @Test
+    fun `preferred ABI reaches the loaded state and universal APKs count as supported`() = runTest {
+        val universalApk = createTestParsedReleaseApk(version = "153.0", abi = UNIVERSAL_ABI)
+        val arm64Apk = createTestParsedReleaseApk(version = "153.0", abi = "arm64-v8a")
+        val userDataRepository = FakeUserDataRepository()
+        val viewModel = createViewModel(
+            releaseRepositories = listOf(
+                FenixReleaseReleaseRepository(
+                    FakeMozillaArchiveRepository(
+                        fenixReleaseVersions = NetworkResult.Success(listOf("153.0")),
+                        fenixReleasesByVersion = mapOf(
+                            "153.0" to NetworkResult.Success(listOf(arm64Apk, universalApk)),
+                        ),
+                    ),
+                ),
+            ),
+            userDataRepository = userDataRepository,
+        )
+
+        viewModel.initialLoad()
+        advanceUntilIdle()
+
+        val initialState = viewModel.homeScreenState.value as HomeScreenState.Loaded
+        assertEquals(UNIVERSAL_ABI, initialState.preferredAbi)
+        val apks = (initialState.apps.getValue(FENIX_RELEASE).apks as ApksResult.Success).apks
+        // Universal bundles every architecture, so it must never be flagged as unsupported.
+        assertTrue(apks.single { it.abi.name == UNIVERSAL_ABI }.abi.isSupported)
+        assertEquals(UNIVERSAL_ABI, apks.preferredAbiApk(initialState.preferredAbi)?.abi?.name)
+
+        userDataRepository.savePreferredAbi("arm64-v8a")
+        advanceUntilIdle()
+
+        val updatedState = viewModel.homeScreenState.value as HomeScreenState.Loaded
+        assertEquals("arm64-v8a", updatedState.preferredAbi)
+        assertEquals("arm64-v8a", apks.preferredAbiApk(updatedState.preferredAbi)?.abi?.name)
+    }
+
     private class FakeHomeDataCacheRepository(
         var snapshot: HomeDataSnapshot? = null,
     ) : HomeDataCacheRepository {
diff --git a/app/src/test/java/org/mozilla/tryfox/ui/screens/SettingsViewModelTest.kt b/app/src/test/java/org/mozilla/tryfox/ui/screens/SettingsViewModelTest.kt
index f9294b9..13e76eb 100644
--- a/app/src/test/java/org/mozilla/tryfox/ui/screens/SettingsViewModelTest.kt
+++ b/app/src/test/java/org/mozilla/tryfox/ui/screens/SettingsViewModelTest.kt
@@ -19,6 +19,7 @@ import org.mozilla.tryfox.download.ApkDownloadRequest
 import org.mozilla.tryfox.download.model.DownloadStatus
 import org.mozilla.tryfox.download.model.PersistedDownloadState
 import org.mozilla.tryfox.model.HomeScreenLayout
+import org.mozilla.tryfox.util.UNIVERSAL_ABI
 import java.io.File
 
 @OptIn(ExperimentalCoroutinesApi::class)
@@ -61,6 +62,45 @@ class SettingsViewModelTest {
         assertEquals(0L, viewModel.uiState.value.cacheSizeBytes)
     }
 
+    @Test
+    fun `preferred ABI defaults to universal and offers every device ABI`() = runTest {
+        val userData = FakeUserDataRepository()
+        val viewModel = SettingsViewModel(
+            FakeCacheManager(tempDir),
+            FakeDownloadCoordinator(),
+            userData,
+            supportedAbis = listOf("arm64-v8a", "armeabi-v7a"),
+        )
+        advanceUntilIdle()
+
+        assertEquals(UNIVERSAL_ABI, viewModel.uiState.value.preferredAbi)
+        assertEquals(listOf(UNIVERSAL_ABI, "arm64-v8a", "armeabi-v7a"), viewModel.uiState.value.abiOptions)
+
+        viewModel.selectPreferredAbi("arm64-v8a")
+        advanceUntilIdle()
+        assertEquals("arm64-v8a", viewModel.uiState.value.preferredAbi)
+
+        // An ABI this device cannot run is never persisted.
+        viewModel.selectPreferredAbi("x86_64")
+        advanceUntilIdle()
+        assertEquals("arm64-v8a", viewModel.uiState.value.preferredAbi)
+    }
+
+    @Test
+    fun `a stored ABI the device no longer runs resolves back to universal`() = runTest {
+        val userData = FakeUserDataRepository()
+        userData.savePreferredAbi("x86_64")
+        val viewModel = SettingsViewModel(
+            FakeCacheManager(tempDir),
+            FakeDownloadCoordinator(),
+            userData,
+            supportedAbis = listOf("arm64-v8a"),
+        )
+        advanceUntilIdle()
+
+        assertEquals(UNIVERSAL_ABI, viewModel.uiState.value.preferredAbi)
+    }
+
     private class FakeDownloadCoordinator : ApkDownloadCoordinator {
         private val states = MutableStateFlow<Map<String, PersistedDownloadState>>(emptyMap())
         override val downloads = states
diff --git a/app/src/test/java/org/mozilla/tryfox/util/AbiPreferenceTest.kt b/app/src/test/java/org/mozilla/tryfox/util/AbiPreferenceTest.kt
new file mode 100644
index 0000000..c734b20
--- /dev/null
+++ b/app/src/test/java/org/mozilla/tryfox/util/AbiPreferenceTest.kt
@@ -0,0 +1,100 @@
+package org.mozilla.tryfox.util
+
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Assertions.assertFalse
+import org.junit.jupiter.api.Assertions.assertNull
+import org.junit.jupiter.api.Assertions.assertTrue
+import org.junit.jupiter.api.Test
+import org.mozilla.tryfox.data.DownloadState
+import org.mozilla.tryfox.ui.models.AbiUiModel
+import org.mozilla.tryfox.ui.models.ApkUiModel
+import org.mozilla.tryfox.ui.models.preferredAbiApk
+import java.io.File
+
+class AbiPreferenceTest {
+
+    private val deviceAbis = listOf("arm64-v8a", "armeabi-v7a", "armeabi")
+
+    @Test
+    fun `universal installs on any device and unknown ABIs do not`() {
+        assertTrue(isAbiSupported(UNIVERSAL_ABI, deviceAbis))
+        assertTrue(isAbiSupported("Universal", deviceAbis))
+        assertTrue(isAbiSupported("arm64-v8a", deviceAbis))
+        assertFalse(isAbiSupported("x86_64", deviceAbis))
+        assertFalse(isAbiSupported(null, deviceAbis))
+    }
+
+    @Test
+    fun `options list universal first then every buildable device ABI`() {
+        // The archive publishes arm64-v8a, armeabi-v7a, x86_64 and universal; legacy armeabi is
+        // still advertised by the platform but nothing targets it, so it is not offered.
+        assertEquals(listOf(UNIVERSAL_ABI, "arm64-v8a", "armeabi-v7a"), abiPreferenceOptions(deviceAbis))
+        assertEquals(listOf(UNIVERSAL_ABI, "x86_64", "x86"), abiPreferenceOptions(listOf("x86_64", "x86")))
+        assertEquals(listOf(UNIVERSAL_ABI), abiPreferenceOptions(emptyList()))
+        assertEquals(listOf(UNIVERSAL_ABI), abiPreferenceOptions(listOf("armeabi", "mips64")))
+        assertEquals(listOf(UNIVERSAL_ABI, "arm64-v8a"), abiPreferenceOptions(listOf("arm64-v8a", "arm64-v8a")))
+    }
+
+    @Test
+    fun `stored affinity falls back to universal when blank or foreign to this device`() {
+        assertEquals("arm64-v8a", resolvePreferredAbi("arm64-v8a", deviceAbis))
+        assertEquals(UNIVERSAL_ABI, resolvePreferredAbi(UNIVERSAL_ABI, deviceAbis))
+        assertEquals(UNIVERSAL_ABI, resolvePreferredAbi(null, deviceAbis))
+        assertEquals(UNIVERSAL_ABI, resolvePreferredAbi("", deviceAbis))
+        // Recorded on an x86 emulator, then restored onto an ARM device.
+        assertEquals(UNIVERSAL_ABI, resolvePreferredAbi("x86_64", deviceAbis))
+        // The device runs armeabi, but it is no longer an option, so it resolves back to universal.
+        assertEquals(UNIVERSAL_ABI, resolvePreferredAbi("armeabi", deviceAbis))
+    }
+
+    @Test
+    fun `installed ABI is read from the native library directory`() {
+        val installDir = "/data/app/~~xY==/org.mozilla.firefox-aB=="
+        assertEquals("arm64-v8a", abiFromNativeLibraryDir("$installDir/lib/arm64"))
+        assertEquals("armeabi-v7a", abiFromNativeLibraryDir("$installDir/lib/arm"))
+        assertEquals("x86_64", abiFromNativeLibraryDir("$installDir/lib/x86_64"))
+        assertEquals("x86", abiFromNativeLibraryDir("$installDir/lib/x86/"))
+        // An unrecognised directory is reported as-is rather than dropped.
+        assertEquals("riscv64", abiFromNativeLibraryDir("$installDir/lib/riscv64"))
+        assertNull(abiFromNativeLibraryDir(null))
+        assertNull(abiFromNativeLibraryDir(""))
+        // A package with no native code has no architecture subdirectory, so no active ABI.
+        assertNull(abiFromNativeLibraryDir("$installDir/lib"))
+    }
+
+    @Test
+    fun `preferred variant wins and universal is the fallback`() {
+        val releaseApks = listOf(apk("arm64-v8a"), apk("armeabi-v7a"), apk(UNIVERSAL_ABI))
+
+        assertEquals(UNIVERSAL_ABI, releaseApks.preferredAbiApk(UNIVERSAL_ABI)?.abi?.name)
+        assertEquals("arm64-v8a", releaseApks.preferredAbiApk("arm64-v8a")?.abi?.name)
+        // x86_64 has no variant here, so the universal APK still installs.
+        assertEquals(UNIVERSAL_ABI, releaseApks.preferredAbiApk("x86_64")?.abi?.name)
+    }
+
+    @Test
+    fun `nightly builds without a universal variant fall back to a supported ABI`() {
+        val nightlyApks = listOf(
+            apk("x86_64", isSupported = false),
+            apk("arm64-v8a"),
+        )
+
+        assertEquals("arm64-v8a", nightlyApks.preferredAbiApk(UNIVERSAL_ABI)?.abi?.name)
+        assertEquals("arm64-v8a", nightlyApks.preferredAbiApk("arm64-v8a")?.abi?.name)
+        assertEquals("x86_64", nightlyApks.preferredAbiApk("x86_64")?.abi?.name)
+        assertNull(emptyList<ApkUiModel>().preferredAbiApk(UNIVERSAL_ABI))
+    }
+
+    private fun apk(abiName: String, isSupported: Boolean = true) = ApkUiModel(
+        originalString = "fenix-153.0-android-$abiName/",
+        date = "",
+        appName = FENIX_RELEASE,
+        version = "153.0",
+        abi = AbiUiModel(abiName, isSupported),
+        url = "https://archive.invalid/fenix-153.0.multi.android-$abiName.apk",
+        fileName = "fenix-153.0.multi.android-$abiName.apk",
+        downloadState = DownloadState.NotDownloaded,
+        uniqueKey = "$FENIX_RELEASE/fenix-153.0.multi.android-$abiName.apk",
+        apkDir = File("."),
+    )
+}