App Manager Tech

A local-only Android app manager / cleaner inspired by SD Maid, for non-root devices. Inspect, batch-act on, and audit every installed app — without sending a single byte off the device.

F-Droid only. No Google Mobile Services, no Firebase, no Internet permission.

---

Highlights

• Inspect every installed app: label, version, install / data / cache sizes, install source (Play / F-Droid / sideload), last-used timestamp, signing certificate SHA-256, requested + granted permissions.
• Batch act: select multiple apps and uninstall / clear cache / force stop in a guided sequence (the OS shows its own per-app confirmation; we never bypass it).
• Background scan: a periodic WorkManager job refreshes the catalogue daily or weekly and posts a single local notification when the total cache size crosses a user-configured threshold.
• Storage analyser: per-category breakdown, top-N largest apps, top-N cache hogs.
• Export: storage report to JSON or CSV via Storage Access Framework — no MANAGE_EXTERNAL_STORAGE needed.
• Ignore list: opt-out specific packages from batch actions and notifications (capped at 500 entries).
• Security audit: surfaces apps with Device Administrator privileges or enabled Accessibility services — common abuse vectors.

---

Stack

Layer	Tooling
Language	Kotlin 2.1.0
Build	Android Gradle Plugin 8.7.3, Gradle 8.11.1, JDK 17
UI	Jetpack Compose Material 3 (BOM 2024.12.01), edge-to-edge
DI	Hilt 2.55 (KSP, no kapt) + Hilt-Work for @HiltWorker
Storage	Room 2.6.1 (app_info v2, additive migrations only) + DataStore Preferences
Background	WorkManager 2.10.0 (on-demand init, no androidx.startup)
Coroutines	kotlinx-coroutines 1.9.0
Logging	Timber 5 (DebugTree in debug, NoOpReleaseTree in release)
Splash	androidx.core:core-splashscreen (transparent icon workaround Android 12+)
Tests	JUnit 5 + Truth + MockK + Turbine + Room-testing + Robolectric

All dependencies are Apache 2.0 / MIT / BSD. Zero proprietary SDK.

---

Architecture

ui/
├── screens/{applist, appdetail, storage, settings, about,
│            cleaner, ignorelist, export, securityaudit}/
│   ├── XxxScreen.kt           Compose UI (TopAppBar + Scaffold + sections)
│   └── XxxViewModel.kt        @HiltViewModel, StateFlow<UiState>, Events Channel
├── components/{dialogs, settings, state}/  Reusable composables
└── theme/                     Material 3 + BrandBlue (#2460AB) + BrandDanger (#C62828)

domain/
├── model/         AppInfo, AppCategory, FilterOptions, StorageReport,
│                  AppAction, AppDetail, ZombieApp, ExportReport,
│                  ScanInterval, ExportFormat, ThemeMode, AppSortOrder
├── repository/    AppInfoRepository, IgnoreListRepository (interfaces only)
└── usecase/       19 use cases — one operation per file, returns Outcome<T>

data/
├── local/
│   ├── db/{entity, dao, dto}/   Room AppInfoEntity v2 + AppInfoDao + AggregateRow
│   ├── datastore/               SettingsRepository (DataStore Preferences)
│   └── db/Migrations.kt         Strictly additive Room migrations
├── repository/    AppInfoRepositoryImpl, IgnoreListRepositoryImpl, AppInfoMapper
└── system/        IntentFactory, NotificationChannels, NotificationHelper,
                   WorkScheduler, workers/BackgroundScanWorker (@HiltWorker)

core/
├── ext/           StringExt (anti-ReDoS regex), FlowExt (oneShotEvents),
│                  TimeConstants (MS_PER_DAY, STATEFLOW_STOP_TIMEOUT_MS, MAX_IGNORED_PACKAGES)
└── result/        Outcome<T> sealed (Success/Failure/Loading) + extensions

di/                4 Hilt @Module: AppModule, CoroutineModule, DatabaseModule, RepositoryModule

Rules (enforced by code review):

1. UI layer never imports android.content.pm.* / android.app.usage.* / anything from data/. Everything goes through use cases.
2. Use cases return Outcome<T> — no exception ever crosses the repository boundary.
3. Repository implementations stay in data/repository/; their interfaces live in domain/repository/. Exception: SettingsRepository is in data/local/datastore/ (documented in code).
4. Room migrations are always additive (ALTER ADD, CREATE INDEX IF NOT EXISTS). fallbackToDestructiveMigration is never used.
5. BrandBlue (#2460AB) for confirmation dialogs and primary CTAs. BrandDanger (#C62828) for destructive intent (uninstall, force stop, disable, delete). Cross-theme constant — never colorScheme.error.

---

Build

# Prerequisites: JDK 17, Android SDK 35
./gradlew :app:assembleDebug         # debug APK (3 ABI splits ~18.9 MB each)
./gradlew :app:assembleRelease       # release APK (R8 minify+shrink, 3 splits ~1.86 MB each)
./gradlew :app:testDebugUnitTest     # JUnit 5 unit tests
./gradlew :app:connectedDebugAndroidTest  # Room CRUD + migration tests (emulator/device)

The release build runs lintVitalRelease, R8 minify with shrink resources, ART profile compilation. APK reduction is ~10× (debug → release) thanks to dead-code elimination and tree-shaking.

---

F-Droid compliance

See FDROID.md for the full distribution policy. Summary:

• No INTERNET permission. The app is strictly local.
• No Google Mobile Services, no Firebase, no Crashlytics, no Play Core.
• No telemetry SDKs of any kind.
• All deps Apache 2.0 / MIT / BSD / LGPL / GPL / AGPL (no proprietary AAR).
• Reproducible builds — pinned AGP / Kotlin / Gradle / JDK; no BuildConfig.BUILD_TIME baked into the APK.

The build is signed by F-Droid; we publish unsigned APKs in GitHub releases for users who want to sideload with our own signature.

---

Permissions

Permission	When	Why
QUERY_ALL_PACKAGES	install-time	Enumerate installed apps via PackageManager
PACKAGE_USAGE_STATS	granted in OS Settings (user opt-in)	Last-used timestamps + StorageStats sizes
GET_PACKAGE_SIZE	install-time	StorageStatsManager cache / data sizes
REQUEST_DELETE_PACKAGES	install-time	Trigger system uninstall dialog
KILL_BACKGROUND_PROCESSES	install-time	Best-effort force-stop
POST_NOTIFICATIONS	runtime (Android 13+)	Cache-threshold notification

Never requested: INTERNET, location, contacts, SMS, calendar, MANAGE_EXTERNAL_STORAGE. The app degrades gracefully if any optional permission is denied (sizes / last-used fall back to 0; notifications stay silent).

---

Security

See SECURITY.md for threat model, cryptographic primitives, audit history, and disclosure policy.

Highlights:

• FLAG_SECURE opt-in to block screenshots and recent-apps previews.
• Room schemas exported and checked into schemas/ for migration tests.
• All Outcome.Failure paths use typed AppError — no PII in error strings.
• Timber is silent in release builds (NoOpReleaseTree).
• R8 with shrink resources for release; ProGuard keep rules audited.

---

Project history

7 phases of structured delivery, each closed with a passing release build and a multi-axis audit (quality + coherence + security):

Phase	Scope
I	Scaffold (Kotlin + Compose + Hilt + KSP) — 49 files, 6 audit fixes
II	Data layer (Room v2 + PackageManager + StorageStats + UsageStats + SD Maid enrichments)
III	8 use cases + filter/sort/storage report models + IntentFactory
IV	4 ViewModels (combine reactive on AppList) + brand identity + splash + logo
V	5 screens Compose + 10 reusable components + i18n FR+EN
VI	11 use cases (zombies, permission filter, ignore list, export, schedule scan) + WorkManager + Notifications
VII	Unit tests + Room CRUD/migration tests + release WorkManager init fix + 9 audit fixes
VIII	4 dedicated screens (Cleaner, IgnoreList, Export, SecurityAudit) + AboutScreen links + 12 audit fixes

Total: 226 i18n strings EN+FR parity 100%, 3 release APK splits 1.86 MB, 0 GMS dependency.

---

Licence

Apache 2.0 — see LICENSE.

Files Tech — France.