Audiokit Unveils Synth One, World's First Professional Open Source iOS Synth

Years in the making, this fully-featured iOS synth not only sounds amazing, it's completely free and open source. This could be the start of something huge.  

Massive news from Audiokit, who have released a project several years in the making - Synth One, the world’s first completely free and open-source full-featured professional iOS synthesizer app. While open source software on the desktop is relatively common, it's much less usual to find it on iOS, especially in the pro audio world. 

Crucially, Synth One is completely free, with no ads, no purchases of any kind and has all the features you'd normally expect from a commercial, paid instrument. It has been developed in consultation with synth techs and sound designers who have worked with M83, Rihanna, Kanye West, Owl City and many more. 

Created by volunteers, the app includes MIDI support (play it with a MIDI keyboard or controller), sequencer, vintage-inspired analog filters, expressive arpeggiators, warm analog delays, and, over 300+ presets to get you started. Plus, it’s completely open-source so you can use the code to learn how to build your own synth app or modify the app yourself. Anyone can contribute code and features!


  • Hybrid Analog/FM Poly Synthesizer
  • Over 300+ Presets crafted by famous sound designers
  • Audiobus 3 & Inter-app Audio (IAA)
  • AUM, BeatMaker 3, Cubasis, GarageBand compatible
  • Five Oscillators (2 DCO, FM, Sub, Noise)
  • 2 Assignable LFOs with dozens of routing possibilities
  • 100+ Alternative Scales & Tunings
  • Vintage-Style 16-Step Sequencer
  • Classic poly arpeggiator
  • MIDI in (Control with a MIDI Keyboard or DAW)
  • Touchable ADSR Envelopes for Amp & Filter
  • FM Oscillator w/ Mod
  • Dedicated Sine/Square -12/24 Sub Osc
  • 4-Pole Vintage Low-Pass Filter
  • High-Pass/Band Pass Filters
  • Mono portamento & legato
  • Beautiful Sean Costello Reverb
  • Multi-tap (ping-pong) delay
  • TouchPads
  • Preset Import/Export & More…
  • MIDI Learn on all knobs
  • MIDI Bank (MSB)/Patch Change & Sustain Pedal support
  • Compact app size (under 50mb)

Upcoming features include:

  • Ableton Link
  • AUv3 Plug-in support to use in your iOS host
  • MPE Midi Support – Expressive control with Roli Seaboard, etc

The app is available to download for FREE:

Find out more at the website:

Learn more about synthesis and iOS in the Ask.Audio Academy:

Rounik is the Executive Editor for Ask.Audio & macProVideo. He's built a crack team of professional musicians and writers to create one of the most visited online resources for news, review, tutorials and interviews for modern musician and producer. As an Apple Certified Trainer for Logic Pro Rounik has taught teachers, professional... Read More


Chris Catalano
Sounds as good as anything on my desktop, including Serum and Falcon. Obviously, being on an iPad the ability to tweak is going to have some limitations, and I believe it is all synthesis (no samples)...but the sound design in the included presets is beautifully done. Because of all the waveforms available, I am thinking maybe wavetable synthesis is a part of this? I just know it is the best free iOS app in the history of the platform, and goes to the top shelf in my Synth folder on iPad. It is free. No IAPs, no catch. A gift.

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