Sonosync - Relaxing music 4+

For sleep and meditation

One In A Billion Ltd

    • 4.6 • 94 Ratings
    • Free
    • Offers In-App Purchases



Music in tune with your resting heartbeat™.
Full album of relaxing music included with the free version. Improve your relaxation and get more refreshing sleep.
Unlock the app to gain extra features: control the music tempo - move to slower tempos as your relaxation improves over time; fade into a deep sleep with the sleep timer; plus lots more photos.

The Sonosync app contains five different musical compositions, each recorded at three different tempos, providing over two hours of music. Our studies have shown that listeners find the version with the tempo closest to their heartbeat to be the most relaxing.

The free version of this app allows you to listen to five full length compositions at the highest tempo. All the music has been mastered for iPhone and iPad listening. We recommend headphones for the best quality, but the mixes have also been optimised for the built-in speakers.

Unlock the extra features and receive the following:

Full control

Get all three variations of each composition. You choose the tempo that is most relaxing for you. Over time you may find you gradually move to the slower versions as your relaxation levels increase.

Each variation was recorded and mixed separately by the composer. There are subtle differences in every recording, in order to make the music work perfectly at each tempo. Every note, beat and echo is in perfect sync!

Drift into sleep

Use the sleep timer to automatically fade out the music and drift into a peaceful sleep.

Get all the photos

You will also receive all 36 beautiful photos which automatically play in the background.

What’s New

Version 1.0.9

- bug fixes
- update UI for iOS 13

Ratings and Reviews

4.6 out of 5
94 Ratings

94 Ratings

Jeff Pham ,

Very good music

I really enjoy the calm music and the relaxing background images. I just have one request and that is to add a repeat track button so the user could repeat a song in a loop.

CL500000 ,

Free version doesn't do much

This app is a pretty decent free app, but it's not much more than an audio player. I didn't see anything that would support the claim of matching your heart rate. And the picture and music selections are pretty limited.

My sense was that you could easily do the same thing with any audio player like the iOS Music app. Having said that, the audio samples the free version has are not bad. The sleep timer is a neat twist.

The frustrating thing was that the app offers the feature in the user interface, not grayed out. Then if you select the feature, such as the tempo, it prompts you to upgrade.

The free version does give one a sense of what the app is all about.

App Privacy

The developer, One In A Billion Ltd, has not provided details about its privacy practices and handling of data to Apple. For more information, see the developer’s privacy policy.

No Details Provided

The developer will be required to provide privacy details when they submit their next app update.

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