Record yourself at the piano.
Hear it played back well.
Rubato is an app for Android phones — the only kind it runs on for now. It listens to a recording of your playing, works out the notes you played, removes what the microphone got wrong, and plays it back through a sampled grand piano or any other instrument — exactly as you played it, tidied up, or shaped the way you ask, with help from an AI.
How it works
Everything below runs on your phone. No account, no upload, no network needed.
Record
Put the phone near the piano and play. Or import something you recorded already — MP3, M4A, MP4 video or WAV.
Convert to notes
A transcription model on the phone turns the sound into notes: pitch, timing, length and how hard each key was struck.
Clean up*
Microphones hear notes nobody played. Sliders remove them, and you can listen to only what was removed, or slow playback down and tap 👻 where you hear one.
Play it back
Hear the take through a sampled grand piano or any other instrument: as played, steadied, or in another style. Edit part by part, note by note, with undo.
* Cleaning up by hand is only expected while the transcription model is still being developed. The aim is for conversion to get the notes right by itself.
Your playing stays yours
Nothing changes without a reason
- Your recording is never altered; it stays as the reference.
- Every correction says what it changed and why, so you can refuse it.
- Cleanup removes doubtful notes. It does not rewrite what you played unless you turn that on.
Shape it with an AI, if you want
- Ask in your own words — “bring out the melody, keep the left hand soft”.
- Each proposed change comes with its reason; untick any you don't want, then listen.
- Save the versions you like and come back to them.
- Rubato is built to work with large language models in general. For now only Claude is supported — with your own Claude API key, or through your own Rubato server added to Claude as a connector. Others are on the way.
Coming next
What is being built now.
Keep the result
Save the digitized, refined take to use elsewhere: as MIDI for any music software, or as audio to share.
Sheet music
Turn a take into a score you can read, print or keep playing from.
Loop mode — first version in testing
Build a piece in layers. Play four bars, digitize them and let them loop; play four more over the top; stack up to ten loops, then play your melody over all of it.
Get the app
Rubato is in testing and runs only on Android for now — there is no iPhone, tablet or computer version yet. Builds live in a private GitHub repository, so the download link works once you have been given access.
- Request access with your GitHub username, below. You need a GitHub account — creating one is free.
- Accept the invitation. GitHub emails you when you are let in; open it and choose Accept.
- Download the newest build. On your phone, open the releases page, pick the top one and tap the file ending in
.apk. - Install it. Android asks before installing an app from outside the Play Store: allow it for your browser when prompted, then tap Install.
Before you have access, GitHub shows “Page not found” there — that is GitHub hiding a private repository, not a broken link. Sign in to GitHub on your phone first.
Request access
Requests are read by hand. When yours is accepted, the invitation comes from GitHub.