keezy - A colorful soundboard. Play with music.
Surge XT - Open-source subtractive-hybrid synthesizer formerly sold commercially as Vember Audio Surge.
SoundGrail - SoundGrail Music App designed for pianists, guitarists, and DJs.
Auxy Music Studio - Auxy brings real music creation to iPhone in a simple and inspiring format.
Aftertouch - Aftertouch – 3D MIDI Controller created and published by Kevin Nelson.
AudioKit Synth One - Free & Open-source iPhone/iPad Synth 🎹