Runxt XY
With Runxt XY you can easily turn your favorite iOS device in a XY MIDI Controller.
Connect your iOS device via CoreMIDI to your Mac or via rtpMIDI on Windows.
Ableton users can easily attach the x- and y-axis to a parameter via MIDI Learn by pressing the colored knobs below the xy-pad. These also function as a 'floor it / pedal to the metal' button.