Auxy Music Studio - Auxy brings real music creation to iPhone in a simple and inspiring format.
FL Studio Mobile - Create & save multi-track music projects on a smartphone
AudioKit Synth One - Free & Open-source iPhone/iPad Synth 🎹
Splice Beat Maker - Make and share beats in your browser
Type Drummer - Drum by typing
GarageBand - GarageBand is a fully equipped music creation studio for Mac