SleepTimer

A fancy sleep timer for Android. Starts a countdown that stops media playback, fades audio out, and optionally locks the screen when it ends — so you can fall asleep without your phone draining the battery or blaring podcasts at 3 AM.

No accounts, no ads, no trackers, no network access.

Features

• Simple countdown timer with +step, −step and cancel actions directly from the notification (step is configurable, defaults to 5 min)
• Shows the exact wall-clock time at which the timer will end
• Stops audio and video playback across apps at the end of the timer
• Configurable fade-out duration before playback stops
• Optional screen lock when the timer ends — choose between Device Admin (standard Android lock, credential required to unlock) or Shizuku soft lock (simulates the power button, biometric unlock keeps working)
• Optional Wi-Fi, Bluetooth, and mobile data off when the timer ends (via Shizuku, since modern Android blocks apps from toggling these directly)
• Six built-in themes (Midnight, Ocean, Ember, Light, Basic, AMOLED) with an optional drifting starfield behind the dial
• Haptic feedback for timer controls (can be disabled)
• Foreground service keeps the timer reliable even when the app is in the background
• English and German translations

Screenshots

Timer running	Settings	Themes

Permissions

The app declares a ShizukuProvider so it can talk to Shizuku when you enable the Wi-Fi off, Bluetooth off, mobile data off, or soft-lock features. Shizuku is optional — the core timer works without it, and the provider is dormant until you opt in.

The app does not request the INTERNET permission. It cannot connect to any network.

Privacy

• No analytics, crash reporting, or telemetry
• No third-party SDKs (no Firebase, no Google Play Services, no ads)
• All settings are stored locally on your device using Jetpack DataStore
• No data leaves your device

Installation

F-Droid

SleepTimer is available on F-Droid:

GitHub Releases

Signed APKs are published on the Releases page.

Building from source

Requirements:

• JDK 17
• Android SDK with platform 36 (compileSdk)
• minSdk is 26 (Android 8.0)

./gradlew assembleRelease

The build is fully reproducible from this repository using a 100% FLOSS toolchain — no proprietary dependencies, no binary blobs.

Project structure

• app/ — Android application module, entry points, DI wiring
• core/data/ — settings and timer state (DataStore + repository pattern)
• core/service/ — foreground service managing the countdown and playback control
• feature/timer/ — Jetpack Compose UI for the timer and settings screens

Written in Kotlin with Jetpack Compose, Hilt (DI) and kotlinx.serialization.

Contributing

Issues and pull requests are welcome at https://github.com/Xitee1/sleep-timer.

License

SleepTimer is free software licensed under the GNU General Public License, version 3 or later. See LICENSE for the full text.

Copyright (C) 2026 Xitee

This program is free software: you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free Software
Foundation, either version 3 of the License, or (at your option) any later
version.

This program is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

Features

• Add option to turn off mobile data when timer ends (requires Shizuku) by @Xitee1 in https://github.com/Xitee1/sleep-timer/pull/61

Fixes

• fix(timer): always show H:MM once the timer reaches 60 minutes by @Xitee1 in https://github.com/Xitee1/sleep-timer/pull/62
• fix(timer): animate the dial at most one revolution by @Xitee1 in https://github.com/Xitee1/sleep-timer/pull/63

What's Changed

• chore(release): bump to 1.3.0 and add F-Droid changelogs (103000) by @Xitee1 in https://github.com/Xitee1/sleep-timer/pull/64

Full Changelog: https://github.com/Xitee1/sleep-timer/compare/v1.2.0...v1.3.0