Overview

Features & Capabilities

MIDIRack is a MIDI toolkit for iPad. Build a custom touch surface from the KB-1 keyboard suite, an all-new sequencer suite, knobs, faders, buttons and more — then unlock a visual MIDI processing graph (one time in-app purchase) and wire it into anything, from a simple custom controller to a full-on groovebox or a self-playing generative composer. Play it on its own and send MIDI anywhere, as an AUv3 plugin in your favourite host or a standalone instrument.

THE BASE APP — PERFORMANCE SURFACE

Design a custom control surface on a snapping grid:

• The KB-1 keyboard suite — piano, diatonic chord pads, scale-locked keyboard, MPE Seaboard ribbon, MPE Strings grid (4ths), and a 4×4 GM drum-pad grid. Each is its own routable node with latch and octave shift. Successor to the KB-1 Expressive Keyboard Suite. • A suite of sequencers — drum, melody, chord, analog and CC step grids and a Matrix note grid, with a moving playhead, swing and microtiming. Per-step velocity, probability, tie and trigger conditions; pattern chaining and 4-pad scene switching for full arrangements; a knob-per-step analog machine that re-roots live as you play. • Knobs, faders, XY pads, buttons and live visualizers — bind to raw MIDI CC or graph parameters.

On its own: a rich custom control surface builder — send MIDI and CC to any synth, app or hardware, no graph required.

WITH YOUR DESKTOP DAW

Expressive MPE hardware costs hundreds. MIDIRack turns the iPad you already own into a controller for Logic, Live, Bitwig, Cubase or any desktop DAW:

• Two MPE surfaces — the Seaboard ribbon and the Strings grid send per-note pitch bend, slide and pressure to any MPE-capable instrument on your desk. • A controller that changes per track — MPE ribbon for the lead, drum pads for the beat, chord pads for the progression, faders mapped to CC for a mix move. Rearrange in seconds; save a surface per project. • Sequence it too — clock the step lanes to your DAW and drive its tracks. • Easy to connect — one USB cable to a Mac via IDAM (Inter-Device Audio and MIDI), or wirelessly over Bluetooth MIDI. No driver, no helper app.

UNLOCK — MIDI GRAPH (in-app purchase)

Wire MIDI In → processors → MIDI Out on a visual canvas:

• 60+ node kinds — arpeggiators, scale/key quantizers, transposers, chords, echoes, swing, humanize, euclidean rhythms, random/generative melodies, LFOs, CC tools, an analog knob-per-step sequencer, a Matrix sequencer and a Counter. • Built-in instruments — Synth, Drums, a Sampler and a loop Slicer make sound right in the graph; no external synth required. • Emergence generators — Conway's Game of Life, Turing machine, Wolfram rules, Markov, bouncing balls, Lorenz attractor — for evolving, living patterns. • Presets — factory patches grouped by category (control surfaces, generators, keyboards, utilities): Amen Engine, Starfield, Conway Choir, Turing Bass, Cellular Drums… Save your own.

ROUTING & MPE

• MIDI Out exposes all 16 channels plus an MPE connector — multitimbral, multi-instrument setups. The built-in synth responds to MPE. • Every keyboard is its own node — process and route each one independently.

PLAYS OUT OF THE BOX

• Built-in polyphonic synth, drum kit, sampler & slicer or send MIDI to your gear via CoreMIDI and an always-on virtual port.

User Growth & Download Statistics

App
By:
Kai Aras
Rating:
4.80
(8)
0.20
Version:
1.1 Last updated: 2026-09-03
Version code:
890723873
Creation date:
2026-08-20
Compatible devices:
Size:
28.33MB
Price:
14.99
URLs:
Website ,Privacy policy
Full description:
See detailed description
Source:
Apple Apps Store
Data ingested on:
2026-09-18
Compare stats and ranking:

Contact the developer

Chrome-Stats does not own this Apple app. Please use these information below to contact the Apple app developer.
Developed by:
Kai Aras
Apple Apps Store
https://apps.apple.com/us/app/midirack/id6779712751
Website:
https://numericalaudio.com/midirack

User Reviews

I really need dotted and triplet notes for all note divisions. It’s something I request for all apps but midi including dotted and triplet notes is perhaps more important to me. Looking forward to see what happens with this app going forward. It reminds me a little bit like working in the note grid for bitwig.
by Ob*****, 2026-09-01

I bought it soon after it was released and loved the deep modular routing possibilities with an intuitive interface. I was concerned when the touch response on the sequencer lanes wasn’t always working . Kai responded instantly to my questions and fixed it days later (works perfect now!) Also, I asked about file management and preset folders and he added that stuff now with the latest update. What more could you ask for from a developer.
by Fl*****, 2026-08-29
View all user reviews ›

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