1. What it does

Plays you a lullaby when you get to bed to help you fall asleep better.

For lullabies, you can use built-in lullabies, your own music, or you can mix in binaural beats.

Built-in lullabies are composed of repetitive sounds making your brain tired and sleepy, and sudden sounds for complete and rich experience stimulating your fantasy.
Five lullabies are build in for free, five additional lullabies available after unlocking the app and many more with the Sleep Lullaby extension pack.

For playing your own music (external player, Spotify, listening to audiobooks), you can use the feature "Turn off when sleeping", which is watching for you falling asleep and then will start a countdown for the set time. After that, it will gradually lower the system media volume.

Binaural beats mix real-time generated binaural tones into lullaby playback. Read more about binaural beats.

2. Where to find it

Settings → Lullaby
Leftmenu → Lullaby (only for selecting or starting lullaby, no settings)

3. Options

Built-in lullabies
  • Whale diving

  • Thunderstorm

  • Mountain stream

  • White noise

  • Down in a cave

  • Fireplace

  • Ocean beach

  • Windy walk

  • Old clock

  • Chants of Tibet

Lullaby Add-ons
  • Summer night

  • Frogs in pond

  • North wind

  • Jungle

  • Lava cake

  • Galloping horse

  • Sheep counting

  • Wind chimes

  • Om chant

  • Temple bells

  • Flute

  • Tribal drums

  • Piano

  • Cat purr

  • Steam train

  • NASA Saturn "sound"

  • Submarine

  • War march

  • Musicbox

  • Baby in belly

  • Girl singing

  • Choir

  • Slow breath

  • Spaceship

  • Brown noise

  • Pink noise

  • Forest

  • Baby Doppler

  • Heart

  • Car

  • Fireworks

  • Fan

  • Hairdryer

  • Shower

  • Shush

  • Vacuum cleaner

  • Washing machine

  • Restaurant

Turn off when sleeping

Controls the system-wide volume level and turns it gradually down when you fall asleep.

Note This feature only works when Sleep tracking is active.
  • Works with built-in lullabies and any sound player app or service.

  • You can set minimal time of playback (0-90 min).

  • To disable this feature, set it to "Use current device volume".


Controls volume of lullabies.

Sudden sounds volume

Controls volume of sudden sounds (e.g. thunders, bubbles).

Start automatically

Initiates lullabies automatically when tracking starts.

Online radio section
+ Online radio

You can add you own online radio

Note You need to find the URL of the online audio stream. This may or may be not the same URL as the radio web player, often the stream URL is hard to find.
Turn off WiFi after lullaby

Turns off the WiFi signal once the volume reaches zero. For online radios and streaming services.

4. Advanced Options

Binaural beats

Enables binaural beats into lullaby playback - effective only if you use the lullaby with headphones.

Warning We do strongly discourage users from using binaural beats if they suffer epileptic or cardiac issues!
  • Delta - frequency goes down to 2 Hz

  • Theta - frequency goes down to 4 Hz


Sets a volume of binaural tones.

Binaural beats in alarm

Configures stimulating binaural beats into alarm sound.

  • Beta - frequency around 20 Hz

  • Gamma - frequency around 40 Hz




Is there any chance to use my own mp3 files for lullabies or use an audiobook player?

You are free to use any mp3 files you like or any player. With the feature Turn off when sleping, just start the playback in your favorite player. Lullaby volume down will take care to bring to volume down after you fall asleep. For more details refer to Lullabies.

Lullabies are recorded

  • Normally if lullaby is played, we stop noise recording, unless you have something plugged into your headphone jack as than we expect you have headphones and we can record normally.

Sonar chirp audible in lullaby

  • We have reports that this can happen on some devices, this depends on how the device mixes audio channels.

  • Try different frequency in Settings → Sleep tracking → Test sensor, frequencies are listed in drop down menu list.

Volume goes down when tracking

If your volume gradually lowers after a while, when the tracking is running, the option Turn off when sleeping is enabled. This feature lowers the system-wide volume, so it affects even music played outside Sleep.

  1. Go to Settings → Lullabies → Turn off when sleeping.

  2. Extend the minimal playback time (5-90 min).

  3. Or disable the feature completely by setting it to Use current device volume.

Volume jumps to max when tracking

Warning The volume needs to be kept at maximum when tracking with sonar for maintaining the reliable results.
  • Unfortunately, this also affects media volume in 3rd party apps, and we cannot control those separately from sonar media volume. This means that while using sonar, you can only use media apps on full volume.

  • You can set a time delay on start of tracking in Settings → Sleep tracking → Awake detection → Delayed sleep tracking.

External players
  • When using sonar, you cannot control media volume by volume buttons as it always jumps back to maximum.

  • You can control volume of lullabies from the Sleep app (Settings → Lullabies), and from the Lullaby add-on pack.

  • When you lower the volume with volume buttons, the lullaby volume is estimated and adjusted accordingly, sonar volume is still kept at maximum.