Hex MIDI: Isomorphic Keyboard
Trung Dung Hoang Music iPhoneiPadiPod touch
Hex MIDI: Isomorphic Keyboard is a free Music app for iPhone and iPad by Trung Dung Hoang. Requires iOS 15.0. Updated October 24, 2026.
- Price
- Free
- on the App Store
- Size
- 62 MB
- Age 4+
- Updated
- Oct 24
- 2026 · v1.0.2
Screenshots
About Hex MIDI: Isomorphic Keyboard
Hex MIDI is an isomorphic MIDI controller and microtonal synthesizer. Instead of the standard piano keyboard, notes are arranged in geometric hexagonal grids - meaning chord shapes, scales, and intervals remain identical across every key. Whether you want to play alternative keyboards like the Wicki-Hayden or Jankó, compose in 19-EDO / 31-EDO microtonal tunings, or control your DAW over MIDI and MPE, Hex MIDI gives you the tools to explore harmony through geometry. Built-In Keyboard Layouts: • Wicki-Hayden – Classic concertina layout with fifths/fourths diagonals and octave columns. • Jankó (Classic & Vertical) – Whole-tone rows with uniform chord fingerings. • Harmonic Table – Euler's Tonnetz grid: major/minor third diagonals with vertical fifths for visual chord building. • Bosanquet-Wilson (Maupin) – Generalized flat-top hex layout built for microtonal navigation. • Harpejji – Whole-tone string layout with semitone vertical progression. • Chromatic Button Accordion – Authentic C-System and B-System (Bayan) layouts. • Fourths & Fifths – String instrument tunings for guitarists, bassists, and violinists. • Major Thirds & Diminished Harmonica – Symmetrical grid layouts. • Custom Layout Editor – Build and save your own hexagonal or rectangular grids. Microtonal & Tuning Engine: • EDO Presets: 19-EDO, 22-EDO (Shruti), 24-EDO (Quarter-tone / Maqam), 31-EDO (Meantone), 41-EDO, 53-EDO, and sub-12 tunings (5-EDO Slendro, 7-EDO, 10-EDO). • Scale Formats: Bohlen-Pierce (13-EDT), Just Intonation, and custom scale generation. • Scala Support: Import standard .scl tuning files and .kbm keyboard mappings. • Visual Color Modes: 5ths spiral color coding, Tonnetz harmonic spectrum, and minimal two-tone palettes. • Note Labels: Display note names with arrow accidentals, Solfège, interval numbers, or exact Hz. MIDI & Expressive Performance: • MIDI I/O: Connect via USB MIDI to hardware synthesizers, external keyboards, and DAWs (Ableton, Logic, Reaper, Bitwig). • MPE & Vibrato: Per-note microtonal pitch-bend routing and touch vibrato. • MTS Support: Real-time MIDI Tuning Standard SysEx transmission for compatible synths. • Touch Control Pads: Integrated dual X/Y pads for assignable pitch, modulation, and CC filters. • Built-In Sound Engine: High-fidelity soundfont player with instant response.
What’s new
Version 1.0.2 · Updated October 24, 2026
- Custom instrument group colors with an interactive color wheel. - Looping Arpeggiator & Strum: Create rhythmic sequences with a looping arpeggiator and dynamic strumming styles. - Chord Progressions & Voicings: Play guided chord progressions, rich jazz voicings, and explore the Circle of Fifths. - Customize accidental notation with sharp #, flat b. - Interactive Training Mode: Learn songs, chords, and scales with guided interactive practice. - 15 Languages & Custom Themes.