Otoo

Otoo is a streamlined, one-screen groovebox designed for frictionless music production.

Built around an innovative free-form step sequencer, Otoo breaks away from rigid grids, allowing you to place, drag, and stack notes freely across independent rows. Whether you are sketching out ideas using the native built-in engine and sampler or hosting your favorite third-party AUv3 plugins, Otoo delivers a distraction-free environment that prioritizes speed and musical flow.

On iPhone, the interface dynamically scales to give your AUv3 instruments a near-fullscreen home, paired with a compact, highly responsive keyboard for immediate creation on the go.

Otoo also includes Otoo MIDI, an AUv3 MIDI processor version of the app. It brings Otoo’s pattern-based sequencing into compatible AUv3 hosts, where playback follows the host timeline and instruments are routed as MIDI Out destinations instead of audio instruments.

Distraction-Free Workflow

• The single-screen layout keeps your sequence, arrangement and mixer visible at all times so you never have to dive into menus.

• A free-form step sequencer lets you place, drag, and stack notes across any row without rigid instrument or track restrictions.

• Step editing mode gives you precise control over note length, velocity, and timing subdivisions.

• The gesture-driven mixer allows for quick volume adjustments, muting, and soloing directly from the main grid.

• 4 rows on iPhone and 5 on iPad, with multiple instruments available in each row at different steps


• 2-octave keyboard for playing and learning real notes

Sounds and plug-ins


• Up to 8 instruments per project


• Built-in sounds and sampler


• Use any installed AUv3 instruments in a large, near-fullscreen view with a compact keyboard


• Up to 2 AUv3 effects per instrument


• Sampler with instant key-by-key recording and chromatic mapping

Patterns to full songs


• Build songs from simple patterns


• Draggable loop markers for quick arrangement changes

Performance mode


• Live sequencer and audio effects such as reverse, beat repeat, randomize, swing, triplet, tape, and more


• Play the pattern like a keyboard by tapping steps directly

Other features

• Main output with built-in level protection

• Automatic metronome when recording live into empty patterns

• Export patterns or full songs as WAV or MP3 for easy sharing

• Export performances as perfect loops

• MIDI export

• Supported time signatures: 4/4, 3/4, 4/4T and sequencer swing.