KeyJaan!

On-device AI turns your songs into a playable rhythm game — tempo, beats and chords. Play with a MIDI keyboard or just tap & swipe. 6 demo songs included.

Your songs become the game.

KeyJaan! is a chord-progression rhythm game that analyzes songs from your own music library — right on your device. Pick a song, and its tempo, beats, bars and chord progression become a playable chart in seconds. No sheet music, no chart downloads.

■ Three ways to play

Plug in a MIDI keyboard and your real playing becomes the score Use the microphone to play with a piano or your voice (experimental) No instrument? Tap the beat and swipe the chords ■ Music theory scores points 7th chords, slash chords, modulations, voice leading — the more musical your playing, the higher the score. Harder songs multiply your points. Left hand rides the beat, right hand sings the melody.

■ The crowd goes wild Ten audience characters react to your playing in real time. Nail a 7th and they'll actually hear it.

■ Records that stack up Achievements, daily streaks, per-song best scores and rankings. Chase that S rank — it's reserved for near-perfect play.

■ 6 demo songs included Original demo tracks are bundled and pre-analyzed, so you can play the moment you download.

■ Private by design Analysis and scoring happen entirely on your device. Your songs never leave it. No data collection, no ads.

FREE: 6 demo songs + analyze up to 5 of your own songs, with a 7-day full-feature trial (1-minute mode stays available afterwards). KEYJAAN PRO (one-time purchase): unlimited analysis + all play lengths. No subscription.

Works with: MIDI keyboards (USB/Bluetooth) / your music library / audio files (mp3, m4a, wav and more) Note: DRM-protected streaming tracks (e.g. Apple Music subscription songs) cannot be analyzed.