Clawtar
The first musical instrument and MIDI controller that adapts to the player's hands.
https://itunes.apple.com/us/app/chordflow/id1219789464?mt=8  

https://itunes.apple.com/us/app/clawtar-adaptive-midi-controller/id1104903396?mt=8
Use your muscle memory 
Clawtar adaptive interface allows you to position your hands on the device the most comfortable and relaxed way. Clawtar ergonomic keys layout facilitates the use of your finger's muscle memory. After some practice you will be able to play with the minimal sight control.

Control other apps or hardware
You can use Clawtar to control your favourite soft or hard synthesizer through Core MIDI connection. 

Features
- Adaptive interface
- Chromatic scale
- 4+ octaves range (8+ with octave shift buttons)
- Pitch-bend control
- Modulation control
- Volume control
- Repeat button (allows to play same note multiple times faster)
- Transposition (allows to change root note)
- 9 built-in sounds.
- CoreMidi support.