The FOSS successor to Greenify — intelligent app hibernation, no root, with UnifiedPush wake-on-push. Built for Android 14/15/16, tested on GrapheneOS / Pixel 8.
| Dashboard | Hibernate | Settings | Push |
|---|---|---|---|
 |
 |
 |
 |
(Shown in French — the app defaults to English and follows your system language.)
Automatically detects unused, battery-draining apps, hibernates them in graduated levels, and guarantees notifications keep arriving thanks to UnifiedPush wake-on-push.
- 0–100 nocivity score per app, broken into 5 transparent components (inactivity, background ratio, CPU wakeups, background network, battery impact). No opaque score — tap it to see the breakdown.
- 5-layer automatic whitelist: system apps, critical roles (dialer, SMS, launcher), active keyboard, accessibility services, password managers, known 2FA apps, VPNs. Signal, Aegis, Bitwarden & co. are protected by default.
- 3 levels: SOFT (RESTRICTED bucket), MEDIUM (+ force-stop on screen off), HARD (+ periodic 6h sweep).
- Auto-hibernation: configurable score thresholds drive automatic hibernation on a periodic sweep — or run a pass on demand.
- Wake-on-push:
FLAG_INCLUDE_STOPPED_PACKAGESdelivers the push even to a force-stopped app — something Greenify never did cleanly. - Battery savings estimate, "wake all" panic button, Quick Settings tile.
A scanner that ranks the apps that woke your phone and used the network while you slept, over a configurable window (4 / 8 / 12 / 24h).
- Per-app wakeup attribution parsed from
dumpsys batterystatsvia Shizuku (wakeupap=history) — validated against real Android 16 output. - Foreground transitions (UsageStatsManager) and background network (NetworkStatsManager) folded into one 0–100 impact score.
- One-tap hibernate straight from a culprit row.
- Honest degradation: without Shizuku, wakeup data is shown as "?" and only foreground + network signals are used.
Volt is a real UnifiedPush distributor: other apps can pick it as their push provider.
- Implements the distributor handshake —
REGISTER→NEW_ENDPOINT,UNREGISTER→UNREGISTERED,REGISTRATION_FAILEDwhen no server is configured. - Persistent WebSocket (TLS 1.3, full-jitter backoff, zero payload logging) to the push server of your choice (NextPush, Gotify, ntfy…).
- Incoming messages (
<token>:<message>over the WebSocket) are routed to the right app and delivered withFLAG_INCLUDE_STOPPED_PACKAGES— the wake-on-push synergy with Hibernate. - Endpoint convention:
wss://host/ws→https://host/UP?token=<token>. Your push server POSTs to that endpoint and forwards<token>:<message>over the WebSocket.
The full distributor protocol is validated on-device (REGISTER/UNREGISTER round-trip, endpoint generation, token→app delivery). Interop with the full range of connector apps is still being tested — treat as alpha.
On Android 16, Volt requires Shizuku to work. This is not a design choice — it's an OS constraint: Google locked the CHANGE_APP_IDLE_STATE permission (not a changeable permission type), and it's no longer grantable via adb pm grant. The only remaining app-level path to manipulate App Standby Buckets is Shizuku, which runs under the shell UID.
Shizuku requires no root, but needs a one-time setup (via wireless debugging or a PC). Volt guides you step by step in the Dashboard tab.
| Android | Shizuku |
|---|---|
| ≤ 15 | optional (reflection path to setAppStandbyBucket still works) |
| 16+ | required for any hibernation |
Download the latest APK from Releases → install it (1 tap). No Android Studio needed.
- Install Shizuku from F-Droid
- Start it via wireless debugging (no PC) — official guide
- Open Volt → Dashboard tab → grant the requested access (the onboarding adapts and disappears once everything is green)
- Hibernate tab → authorize Volt in Shizuku → pick your apps
git clone https://github.com/lebiggg/volt
cd volt
./gradlew :app:assembleDebug
adb install app/build/outputs/apk/debug/app-debug.apkZero telemetry. No network connection beyond the outgoing UnifiedPush WebSocket you configure.
| Permission | Type | Why |
|---|---|---|
INTERNET |
normal | Outgoing UnifiedPush WebSocket |
FOREGROUND_SERVICE_DATA_SYNC |
normal | Persistent network service |
POST_NOTIFICATIONS |
runtime | Minimal service notification |
PACKAGE_USAGE_STATS |
special access | Nocivity score (UsageStatsManager) |
QUERY_ALL_PACKAGES |
normal | List installed apps |
REQUEST_IGNORE_BATTERY_OPTIMIZATIONS |
normal | Service longevity |
RECEIVE_BOOT_COMPLETED |
normal | Opt-in start on boot (off by default) |
The privileged action (am set-standby-bucket) goes through Shizuku, not a direct Volt permission.
ui/screens/ Dashboard | Push | Hibernate (3 tabs) + Settings
ui/theme/ Dynamic Material You (GrapheneOS-friendly)
BatteryCommandService dataSync foreground service, FLAG_INCLUDE_STOPPED_PACKAGES
PushConnectionManager OkHttp WebSocket, full-jitter backoff, zero payload logging
ScreenStateReceiver ACTION_SCREEN_ON/OFF → triggers the sweep
BootReceiver opt-in service start on boot
VoltTileService "Hibernate now" Quick Settings tile
data/hibernation/
├── HibernationController Single facade (idempotent, thread-safe, Shizuku-first)
├── HibernationDecisionEngine Score → level
├── AutoHibernationRunner Wires the engine to the periodic sweep
├── HibernationRepository Entity ↔ Policy bridge (Room)
├── HibernationWorker Periodic 6h sweep (WorkManager)
├── SavingsEstimator Indicative battery savings model
├── nocivity/NocivityScorer 0-100 score in 5 components
├── whitelist/WhitelistResolver 5-layer protection
├── shizuku/ShizukuGateway am set-standby-bucket / force-stop via Shizuku
└── persistence/ Room database
VoltContainer Minimal service locator (no Hilt)
Every bucket operation goes through one point: HibernationController. That's the central invariant — a single file to touch if the system API changes.
./gradlew :app:testDebugUnitTest # pure-JVM models (30 assertions)
./gradlew :app:connectedAndroidTest # integration (device required)CI runs build + unit tests on every push via GitHub Actions.
# Prereq: Shizuku started and Volt authorized.
# Verify an app moves to the restricted bucket after hibernation:
adb shell am get-standby-bucket org.fdroid.fdroid # → 45 (RESTRICTED) after a SOFT in VoltSee CONTRIBUTING.md.
Missing a 2FA / password manager / encrypted messenger in CuratedWhitelist.kt? Open a PR with the packageName, the source-repo link, and a justification.
Volt assumes: an up-to-date GrapheneOS device, a user willing to set up Shizuku once, a trusted UnifiedPush server.
Volt does not protect against: a physical attacker with ADB access, a network MITM without certificate pinning (enable it manually in PushConnectionManager), an app that roots itself (out of scope — see GrapheneOS Auditor).
- Hibernate — engine, whitelist, scoring, UI, Shizuku
- Quick Settings tile
- Battery savings estimate
- Auto-hibernation wired to the periodic sweep
- Internationalization (English + French)
- Opt-in start on boot
- Forensics — nightly wakeup analyzer
- UnifiedPush distributor —
REGISTER/UNREGISTERhandshake - UnifiedPush — broad connector-app interop testing
GPL-3.0 — see LICENSE.
Made with anger at battery drain and respect for your privacy.