KeyJaan!
Your songs become the game
Free · In‑App Purchases
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.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
The developer, Mamiko Tsukamoto, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Mamiko Tsukamoto
- Size
- 93.9 MB
- Category
- Music
- Compatibility
Requires iOS 17.0 or later.
- iPhone
Requires iOS 17.0 or later. - iPad
Requires iPadOS 17.0 or later. - Mac
Requires macOS 14.0 or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
- English and Japanese
- Age Rating
4+
- 4+
- In-App Purchases
Yes
- KeyJaan Pro $9.99
- Copyright
- © 2026 TrueMmedical Inc.