Harmodus Piano - Pure Tuning
Just Intonation & Polyrhythms
Free · In‑App Purchases · Designed for iPad. Not verified for macOS.
All features, free on 25 keys (C3–C5), with no time limit. Buy once to unlock the full keyboard and scrolling. Existing purchases remain valid.
Harmodus Piano is a piano keyboard and metronome app with just intonation.
JUST INTONATION
• Real-time retuning: the app analyzes the chord you hold and applies pure frequency ratios to its root.
• Switch between Equal, Just Major and Just Minor.
• Adjustable reference pitch.
CHORD DETECTION
• 17 chords detected in real time from the notes you play.
• Works with the on-screen keyboard and external MIDI.
18 SOUND SOURCES
• Acoustic and synthesizer timbres — organ, clarinet and more, plus waveforms such as sine and sawtooth.
• Damper pedal with natural resonance.
METRONOME
• 6-track mixer: accent, quarter, eighth, sixteenth, triplet and a custom n-tuplet.
• Odd meters (5, 7, …) add a second accent automatically.
• Tuplets and 2-beat n-tuplets (e.g. half-note triplets).
• A/B alternating patterns, tap tempo, count-in and auto-stop.
• Visible edge-flash and per-track click sounds.
MORE
• Touch and MIDI keyboard (Bluetooth or cable).
• Transpose, sustain / latch.
• 34 languages.
Purchase information:
All features are free with the 25 keys from C3 to C5 (including black keys), with no time limit. A one-time purchase permanently unlocks the full keyboard and keyboard scrolling; an active monthly or annual subscription also unlocks them. Existing one-time purchases and active subscriptions remain valid.
Eligible new users may be offered a 7-day free trial with either the monthly or annual plan. The one-time purchase does not auto-renew.
Terms of Use (Apple Standard EULA):
https://www.apple.com/legal/internet-services/itunes/dev/stdeula/
Privacy Policy:
https://harmoduspiano.musicatechlab.com/privacy/
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
• All features are free with the 25 keys from C3 to C5 (including black keys), with no time limit. A one-time purchase permanently unlocks the full keyboard and keyboard scrolling; an active monthly or annual subscription also unlocks them. Existing one-time purchases and active subscriptions remain valid.
• Improved the welcome screen and lock indicators. Tap the chord display to switch between sharp and flat spellings.
The developer, Jumpei Yamaguchi, 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
- Jumpei Yamaguchi
- Size
- 155.7 MB
- Category
- Music
- Compatibility
Requires iOS 16.0 or later.
- iPhone
Requires iOS 16.0 or later. - iPad
Requires iPadOS 16.0 or later. - Mac
Requires macOS 13.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
English and 32 more
- English, Arabic, Catalan, Croatian, Czech, Danish, Dutch, Finnish, French, German, Greek, Hebrew, Hindi, Hungarian, Indonesian, Italian, Japanese, Korean, Malay, Norwegian Bokmål, Polish, Portuguese, Romanian, Russian, Simplified Chinese, Slovak, Spanish, Swedish, Thai, Traditional Chinese, Turkish, Ukrainian, Vietnamese
- Age Rating
4+
- 4+
- In-App Purchases
Yes
- Lifetime Unlock $6.99
- Yearly Plan $2.99
- Monthly Plan $0.49
- Copyright
- © 2026 MusicaTechLab
