# Harmony Keyboard — Just Intonation Trainer

> Just Intonation Trainer (iPhone/iPad app by SINCLAIR SYSTEM.)

- Source: https://appshunter.io/ios/app/harmony-keyboard/id6745786039 (this page in markdown: same URL + `.md`)
- Developer: [SINCLAIR SYSTEM](https://appshunter.io/developer/1794147761)
- Category: Music, Utilities
- Price: Free with in-app purchases
- Age rating: 4+
- Requires: iOS 15.0 · 45 MB
- Languages: American English, Japanese
- Released: 2025-08-13
- Data updated: 2026-09-05
- User reviews in markdown: https://appshunter.io/ios/app/harmony-keyboard/id6745786039/reviews.md

## What is Harmony Keyboard?

Train perfect intonation with just intonation.

Harmony Keyboard is a powerful practice tool designed for musicians who want accurate tuning and beautiful harmony. It helps you hear and practice chords using both just intonation and equal temperament, making it ideal for ensemble rehearsal, wind band practice, choir training, and ear training.

Whether you're a student, performer, or teacher, Harmony Keyboard helps develop a better sense of pitch and harmonic balance.

KEY FEATURES

• Just Intonation & Equal Temperament
Switch between tuning systems to understand how harmony and tuning work in real music.

• Intonation Training
Practice tuning chords and intervals to develop a precise musical ear.

• Instant Transposition
Transpose instantly to any key for flexible practice.

• Hold Function
Sustain notes and chords while listening carefully to intonation and balance.

• Wind Instrument Sounds
Includes sounds such as flute, clarinet, and saxophone for realistic ensemble practice.

• Customizable Tuning
Adjust reference pitch (e.g. A=442Hz) and note name display.

PERFECT FOR

• Wind band practice
• Brass and woodwind players
• Choir rehearsal
• Ear training
• Music students and teachers

Harmony Keyboard is a simple yet powerful tool for musicians who care about tuning, harmony, and musical precision.

## Pricing and in-app purchases

Base price: Free.

**Subscriptions**

| Subscription | Price | Period |
| --- | --- | --- |
| Pro Version | $0.49 | per month |



## Version history (last 5 releases)

### 1.6.1 — 2026-09-02

Optimized internal processes and improved app stability.

### 1.6.0 — 2026-08-11

Improved stability and made minor enhancements.

### 1.5.0 — 2026-03-16

• Fixed an issue where sound might not play in Silent Mode
• Improved audio stability

### 1.4.0 — 2026-02-01

Minor fixes.

### 1.3.0 — 2025-10-07

Minor fixes.

## Apps similar to Harmony Keyboard

| App | Rating | Price | Category |
| --- | --- | --- | --- |
| [Pitch trainer - Harmonize](https://appshunter.io/ios/app/pitch-trainer-harmonize/id965614965) | 4.4 (412) | Free | Music |
| [Super Wind Orchestra Piano](https://appshunter.io/ios/app/super-wind-orchestra-piano/id1640956919) | 5.0 (6) | Free | Music |
| [Red Koto](https://appshunter.io/ios/app/red-koto/id387575031) | 1.0 (1) | $8.99 | Music |
| [Sightreading Exercises](https://appshunter.io/ios/app/sightreading-exercises/id6446806038) | 4.4 (21) | Free | Music |
| [Tonica - Harmonic training](https://appshunter.io/ios/app/tonica-harmonic-training/id1003005644) | — | Free | Music |
| [KotoTunings](https://appshunter.io/ios/app/kototunings/id380669286) | 5.0 (1) | $8.99 | Music |

## More apps by SINCLAIR SYSTEM

- [Metronome: Rhythm Design](https://appshunter.io/ios/app/metronome-rhythm-design/id6741431186)

All apps by SINCLAIR SYSTEM: https://appshunter.io/developer/1794147761

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-09-05.*