7 Omnichord Apps for iPhone, Compared Side by Side

The closest Omnichord app for iPhone is C.ARP ($9.99), with chord buttons, a strum area and a rhythm section that follows your chords. Omnisound ($0.99) is the one to pick if you record in GarageBand, and Omni: Pocket Synth is the best free start. All seven apps below put a whole chord under one button and give you a way to sweep or strum it; the last two lean toward the acoustic autoharp the Omnichord was built to imitate. We make one of them, Gelato Chord, so it is marked “ours” at number 4.

Is there an official Omnichord app?

No. Suzuki introduced the Omnichord in 1981 and announced a new model, the OM-108, in 2024, but it has no app on the App Store. The apps that fill the gap come from small developers, and they copy the instrument’s three parts: a grid of chord buttons (major, minor and 7th on the classic models), a touch strip called the Sonic Strings that plays the notes of the held chord across four octaves, and a rhythm box with an auto-bass line. The strum plate matters most, because that shimmering sweep is the sound people are chasing.

Five of the seven also run on iPad, and three of those run on Apple silicon Macs too; the spec line under each entry says which. Prices for the other six are US App Store prices, checked in September 2026.

Omnichord apps for iPhone and iPad compared

1. C.ARP (Paolo Giorgi). Paid, $9.99, no in-app purchases. iPhone, iPad and Apple silicon Macs.

   C.ARP names old keyboards, omnichords and tape effects as its inspiration. It first came out in 2019 and is still updated (version 4.72 arrived in July 2026). You hold a chord button, then swipe or tap to play it, while a rhythm section follows every chord you choose, with its own styles, tempo and drum pads. Arpeggios, a mod wheel, delay, reverb and a rotation effect are built in, and a sampler turns a recording of your voice into something you can play chords with. It can also send MIDI over Bluetooth to a Mac, so the same chord buttons can play a synth in your DAW.

2. Omnisound (Konstantin Torsten Schutz). Paid, $0.99, no in-app purchases. iPhone, iPad and Apple silicon Macs, standalone or as an AUv3 plugin.

   The newest app here, released in June 2026 and modeled on the synth-harps of the 1980s: tap a chord, sweep the strings, add a rhythm. An update later that month made it an AUv3 plugin with MIDI in and out, so it loads inside GarageBand or AUM on your iPhone (and Logic Pro on iPad or Mac). There you can record strums straight into a project, or play it from a MIDI keyboard. At $0.99 with nothing to upgrade, it is the easiest one to try if you already record in GarageBand.

3. Omni: Pocket Synth (Ruben Terron Rodriguez). Free with an in-app purchase (Omni Pro, $8.99). iPhone and iPad.

   Omni gives the chords and the strum separate voices with their own sound controls, built on two small synth engines (wavetable and virtual analog). That lets you put a soft pad under a bright plucked strum, much like the organ-style chords and harp-like sweep of an original Omnichord. The strum area offers Standard, Extended, Pentatonic, Scale and Chromatic touchplates, and there is an arpeggiator with swing plus a basic kick and snare. Pro adds the advanced strum modes, a layout editor for your own chord sets, MIDI out and AUv3.

4. Gelato Chord (ours) (Gelato Audio). Free with one $4.99 in-app purchase. iPhone.

   It trades the Omnichord’s grid for seven keys that always play the seven chords of your key, so in G major you get G, Am, Bm, C, D, Em and F#dim, and nothing clashes. In place of a strum plate there is a melody plate: the key’s scale as twelve strings, with the notes of the held chord lit up, so a sweep plays a run and a tap plays one note. The trade-off is one key at a time, so a borrowed chord such as F in G major means changing the key or scale first. The free version is the whole instrument in Play mode with three sounds; the unlock adds Strum mode (which rolls the chord like a harp), Arp, all 59 sounds and a loop recorder with drum grooves.

5. Harmonique (fourtrack.fm). Free with an in-app purchase (Lifetime Unlock, $4.99). iPhone, iPad and Apple silicon Macs.

   Harmonique leans toward the chord-organ side of the Omnichord: two columns of chord buttons, major and minor, with piano keys above them for melodies. A long press drones a chord hands-free, and Perform patterns strum or arpeggiate it in styles like Folk and Bossa Nova at any tempo. A 7th toggle adds sevenths to the chords, a circle-of-fifths picker changes key, and built-in lessons cover chord progressions and borrowed chords. It also runs as an AUv3 and has an audio looper that records from the microphone. If you want to learn why chords fit together while you play them, start here.

6. AutoArp (Drew Milloy). Free with a $0.99 in-app purchase. iPhone only.

   First released in 2011, AutoArp sits halfway between an autoharp and an analog-style synth: pick a chord and brush the strings, with square, pulse or saw waves, a resonant low-pass filter, tremolo and echo. The free version plays a fixed set of songs, each one a preset group of chord buttons. The unlock lets you build your own songs with up to 16 chords from 22 chord types (including a major 7th with a sharp 11th), each with its own bass note, and adds transposing and MIDI. Its last update was in March 2020, so play the free version on your phone for a while before paying for the unlock.

7. Autoharp (Arlo Leach). Paid, $1.99, with optional in-app purchases. iPhone and iPad, plus an Android version.

   The pick if you want the acoustic sound the Omnichord was imitating. It is built on recorded samples, sets the volume by how fast you strum, and comes with the standard 15-bar and 21-bar layouts. Chorus, delay and reverb are built in, and it can act as a MIDI controller for other synths.

Free Omnichord apps for iPhone (and a browser version)

Of the apps from other developers, three cost nothing to start. Omni: Pocket Synth’s free version covers the core chord and strum playing. Harmonique’s free tier includes five instruments, drone mode, a chord progressions lesson and full chord and melody playback. AutoArp’s free version plays its fixed set of songs. GarageBand is a fourth free route.

If you would rather not install anything, our free online chord player runs in the browser. Choose the Pluck sound with strum, pick triads or 7ths, and play in any of the 24 keys. For a first loop, open the chords in G major and play G, Em, C and D, one bar each, to hear how a strummed chord carries a song on its own.

How to get the Omnichord sound in GarageBand

GarageBand has no strum plate, but its chord strips cover most of the Omnichord’s job.

Chords and auto-bass. Add a Keyboard track, pick an organ or soft synth sound (the original Omnichord’s chords were organ-like), and tap the Chord Strips button. Each strip holds one chord. The five upper segments play it higher or lower, the three lower segments play bass notes, and tapping one of each together gives you chord plus bass. Turn the Autoplay knob to a numbered position and the strip plays a comping pattern for you, the nearest thing GarageBand has to the Omnichord’s auto-accompaniment.

The strum. Switch to the Guitar, tap Chord Strips, and swipe across the strings inside a strip. That is the Sonic Strings motion, with a guitar sound. For a harp-like tone, go back to the Keyboard, pick a bright synth and open the Arpeggiator: turn on Run, set Note Order to go up, choose a fast Note Rate such as 1/16, and use the widest Octave Range, since the real plate spans four octaves. The arpeggiator ignores chord strips, so hold C, E and G on the keys, then lock the Latch control, and the arpeggio keeps going after you let go. One catch: tapping a new key moves the same chord shape there, so a latched C major arpeggio becomes F major on F, but A major on A. For Am, release the latch and play A, C and E.

The rhythm box. Add a Drummer track and keep the pattern simple so the strum stays in front.

Or load an Omnichord app. If you own Omnisound, or Omni with Pro, GarageBand can host it. In the Sound browser, swipe to External, tap Audio Unit Extensions and pick the app. GarageBand then records it like any Touch Instrument.

Autoharp apps that strum the same way

The Omnichord was conceived as an electronic autoharp, so autoharp apps use the same motion: hold a chord, brush the strings. On a real autoharp, each chord bar carries felt pads that mute every string outside the chord, so a sweep across all the strings only sounds that chord. The apps do the same job without the felt.

Autoharp by Arlo Leach is the most faithful of them, down to muted strings and stopping strings with extra fingers. If you own a real autoharp, its $3.99 layout purchase lets you set the note of every string (from 53 choices) and the strings each bar plays, so you can try a new setup before you change the real one.

If six buttons are all you need, iAutoharp from HotPaw Productions ($1.99, iPhone and iPad) is the simpler take. It models a 37-string instrument, starts with six common chords that you can reassign to any of more than 150 per key, and lets you pick out a melody by pinching a few strings with two fingers.

A pattern that works on all of them: in 4/4, sweep low to high on beats 1 and 3, then brush only the top few strings on 2 and 4. In 3/4, play one full sweep and two short brushes up high, which is the whole waltz feel. Try it over G, C and D before adding a fourth chord.

If the app bug turns into a hardware itch, our guide to Omnichord alternatives that cost less covers the physical options.