Mother MIDI
A MIDI chord generator eternally devoted to your synthesizers.
Chord Generator
Sacred harmonies.
Touch the root key, a chord button, and extension to build rich chords. Double-tap to latch.
And each of the four chord and four extensions slots are fully customizable.
Arpeggiator
A litany of notes.
Six rates, four patterns, and one to three octaves, with Root +12 and double notes. Sync'd to your hardware or software MIDI clock.
Expression
A touch of the divine.
Velocity sensitive from bottom to top, set with a customized range. Drag up on a held key to raise modulation, down to lower it. And a pitch wheel for bends.
Inversions
Three voices in one.
Each key holds up to three zones: root position, first inversion, and second inversion. Where you touch the key decides which voicing sounds.
Destinations
Submit to her will.
Send MIDI to any of your connected hardware or software instruments. To reach a DAW on a Mac, connect a cable and enable the device in Audio MIDI Setup. The setup guide has the rest.
Lineage
Born of Best Friend.
Mother MIDI began as the Chord Generator inside Best Friend, the unrivalled companion app for Teenage Engineering EP-Series samplers. Now she answers to any hardware of software instrument that speaks MIDI.
Features
The complete canon.
Chords
Full voicings from a single root key.
- Four chord slots and four extension slots
- Hold a chord with any root key to play it
- Double-tap to latch a chord; tap another to move the latch
- Extensions stack — hold as many as you like
- Edit any slot: up to 5 notes across two octaves
- Suboctave of the root on a single toggle
- Pitch wheel bends ±2 semitones
Expression
Velocity, modulation, and chord voices.
- Velocity sensitive from touch position, with a settable range
- Modulation from vertical drag on a held key
- Keyboard zones for root position, 1st and 2nd inversion
- Twelve keys, a sliding range, and an octave stepper
- Hardware keyboard play in the Musical Typing layout
Arpeggiator & MIDI
Follows your clock and sends where you choose.
- Rates of 4, 8, 8T, 16, 16T and 32
- Up, Down, Up-Down and Down-Up patterns across 1–3 octaves
- Root +12 and double notes
- Follows incoming MIDI clock from a DAW or hardware
- MIDI channel 1–16
- Send to every destination, or only the ones you pick
Catechism
Questions, answered.
What is Mother MIDI?
Mother MIDI is a MIDI controller and chord generator for iPhone and iPad. Hold a chord button and touch a root key, and it sends the full chord — or an arpeggio of it — to any synth, app, or DAW that takes MIDI.
Does Mother MIDI make any sound?
No. Mother MIDI sends MIDI only. Pair it with a hardware synth, an instrument app such as GarageBand, or a DAW on your Mac.
What can it control?
Anything that receives MIDI: hardware connected by cable, other music apps on the same device, and DAWs on a Mac. It sends to every connected destination by default, or only the ones you choose, and it also shows up in other apps as a MIDI source called Mother MIDI.
How do I use it with Logic Pro, Ableton Live, or FL Studio?
Connect your iPhone or iPad to the Mac with a cable, open Audio MIDI Setup, choose Window > Show Audio Devices, select your device, and click Enable. Your DAW then lists a MIDI port named after your iPhone or iPad. The DAW guide covers each DAW step by step, including sending clock back for the arpeggiator.
Why is the arpeggiator silent?
The arpeggiator follows an incoming MIDI clock — Mother MIDI doesn't make one of its own. Send clock from your DAW or hardware and press play. The Arp tab of Settings shows which clock it is following. Chords and single notes never need a clock.
Does it work with GarageBand?
Yes. On iPad, open Mother MIDI in Split View beside GarageBand — no cable needed. On a Mac, GarageBand hears it as soon as the device is enabled in Audio MIDI Setup. GarageBand doesn't send MIDI clock, so the arpeggiator won't run, but chords and notes play as normal.
Can I play it from a computer keyboard?
Yes. With a keyboard connected to your iPhone or iPad, the keys follow Logic Pro's Musical Typing layout: A through ' play notes, Shift and Option pick inversions, 7–0 choose chords, 1–4 add extensions, Z and X change octave, and Space toggles the arpeggiator.
How is it related to Best Friend?
Mother MIDI is extracted from Best Friend, the companion app for Teenage Engineering EP-Series samplers, as a standalone MIDI controller. Same developer, same keyboard.
What does it cost?
$6.99 USD, once. One purchase covers iPhone and iPad. No subscription, no in-app purchases, no ads. Requires iOS or iPadOS 26 or later.
Mother is waiting.