reTONE
In development · coming soonFree · Android 4.0+

We don’t cut corners
on sound.

Even an old phone sounds different depending on how it’s driven.That’s where reTONE has spent its time.

Convert once.
Carefully.

Older Android phones convert even CD-quality 44.1 kHz tracks to 48 kHz.If it can’t be avoided, reTONE does it once, and does it properly.

0 dB−6−120 kHz5 kHz10 kHz15 kHz20 kHz
reTONEAndroid 5+ (no setting)Android 4.x (no setting)
Frequency response when converting 44.1 kHz to 48 kHz. The two Android lines are calculated from Android’s public source code (AOSP) for phones with no conversion quality setting. The actual quality depends on each phone maker’s setting: of the phones we checked, two on Android 4.4 were set to a higher quality, and three on Android 5 or later had no setting.
Flat to 20 kHz

Without a setting, Android rolls off the highs

Aliasing below −100 dB

Kept out of the audible band

Converted once at most

Android doesn’t convert again

Response published

Formulas included

Plays what
your phone can’t.

Hi-res FLAC, DSD, AIFF, ALAC.reTONE’s own engine reads them, even on Android 4.1.

FLAC 24/192DSF DSD256DFFAIFFALAC 24/96WAV 32F/384

The engine is written in C. Even a two-core test phone from 2012 plays DSD64 and 24-bit/192 kHz tracks.

Straight to
your USB DAC.

Sent over OTG straight to the DAC, bypassing Android’s audio processing.If the DAC accepts the track’s rate, nothing is converted.

An Xperia P connected to an OPPO HA-2 (3D illustration)
Bypasses Android

No mixer, no resampling

Native DSD

On supported DACs

Volume inside the DAC

No bits lost, on supported DACs

Tested pairings, published

Phones and DACs

DIRECT
means direct.

The bottom row of the player screen shows the track’s format and where it’s going.If a path is known to convert the audio, it won’t say DIRECT. Values it can’t read are never guessed.

FLAC 16/44.1 → 3.5mm STEREO • 48 kHz

FLAC 24/96 → USB AUDIO • 96 kHz DIRECT

DSD64 → USB AUDIO • DSD64 DIRECT

Stop the music,
and it stops too.

Stop playback and reTONE uses 0% CPU.With the screen off, it draws nothing at all. Good for old batteries, and for the sound.

Your everyday phone,
now the remote.

Connect over Bluetooth, and your everyday phone can browse the old one’s library, pick tracks, and control playback and volume.Leave the old one in your bag and control it from the phone in your hand.

A Galaxy S8 in hand controlling reTONE on an Xperia P (3D illustration)
The library in your hand

Pick from albums, rearrange Up next

Volume keys

On your everyday phone

Bluetooth only

No Wi-Fi or internet needed

Remote mode

reTONE on both phones (Android to Android)

On newer Android, too.

reTONE runs on recent phones as well, and adapts its output and layout to the device.

reTONE on a tablet in landscape (three columns), an unfolded foldable (two columns) and a phone. Real screens captured on an Android 15 device; 3D illustration
Direct output

Plays at the track’s own rate. Android 10 and later; availability depends on the phone

Tablets in landscape

Library and player side by side

Foldables

Two columns on the unfolded screen

Things we found
along the way.

Read the devlog ›

Enough talk.
Now go listen.

…Still here?
For those who want more.

What follows may thrill no one but the person who made it.