Custom alarm sounds

Silent alarms

Set silent: true in either platform’s options when the alarm should present normally without playing audio:

await AlarmScheduler.scheduleAlarmAsync({
  hour: 7,
  minute: 0,
  ios: { silent: true },
  android: { silent: true, vibrate: true },
});

silent takes precedence over soundUri and soundName. On Android it skips audio playback and alarm-volume enforcement; vibrate remains independent, so silent: true, vibrate: true is a vibrate-only alarm. The notification and full-screen ringing UI still appear.

On a physical iOS 26+ device, the package uses its own bundled silent CAF while AlarmKit continues to own the alert presentation and vibration. The config plugin adds this asset automatically. If the asset is missing, scheduling fails instead of falling back to an audible system sound.

User-selected audio

Use any document or media picker that returns a readable local URI. With Expo, install the SDK-matched document picker:

npx expo install expo-document-picker

Then pass the selected URI directly to the alarm:

import * as DocumentPicker from 'expo-document-picker';
import AlarmScheduler from 'react-native-alarm-scheduler';

const result = await DocumentPicker.getDocumentAsync({
  type: 'audio/*',
  copyToCacheDirectory: true,
});

if (!result.canceled) {
  await AlarmScheduler.scheduleAlarmAsync({
    hour: 7,
    minute: 0,
    soundUri: result.assets[0].uri,
  });
}

soundUri is common to both platforms. You may instead set ios.soundUri or android.soundUri when the platforms should use different files. Each alarm can use a different URI.

The scheduler imports the audio while scheduleAlarmAsync runs, so the alarm does not depend on a temporary picker permission or cache file later:

• iOS: converts the first 29 seconds to a PCM CAF file in the app’s Library/Sounds directory, which AlarmKit can resolve while the app is not running.
• Android: copies the original into the app’s private files directory and loops it through the native alarm audio stream.

The imported copy is replaced when the same alarm id is rescheduled and removed when the alarm is cancelled. The source file may be moved or deleted after scheduling.

Build-time bundled sounds

Bundled sounds remain useful when the developer owns the fixed sound catalog. On iOS, add compatible sound files to the config plugin:

{
  "expo": {
    "plugins": [
      [
        "react-native-alarm-scheduler",
        { "iosAlarmSounds": ["./assets/audio/morning-alarm.caf"] }
      ]
    ]
  }
}

Reference the exact filename:

await AlarmScheduler.scheduleAlarmAsync({
  hour: 7,
  minute: 0,
  ios: { soundName: 'morning-alarm.caf' },
});

On Android, place the file in android/app/src/main/res/raw and use its resource name:

await AlarmScheduler.scheduleAlarmAsync({
  hour: 7,
  minute: 0,
  android: { soundName: 'morning_alarm' },
});

For audible alarms, runtime soundUri takes precedence over bundled soundName; silent takes precedence over both.

Staying audible on Android

Playback loops on STREAM_ALARM, which ignores the ringer and Do Not Disturb. On top of that, the package defends against the volume-down escape hatch:

await AlarmScheduler.scheduleAlarmAsync({
  hour: 7,
  minute: 0,
  android: {
    enforceVolume: true,
    restoreVolume: true,
    volume: 1,
    vibrate: true,
  },
});

With enforceVolume on, the alarm stream is pinned at volume for the duration of the ring and re-raised whenever anything lowers it. The user’s original level is restored afterwards unless restoreVolume is false.

iOS alarm volume is owned by AlarmKit and is not configurable from the package.