GravSynth is an analog synthesizer for the iPhone & iPod Touch that features both touch and tilt control allowing you to intuitively play a variety of phrases.
1) Analog Synthesizer can be played by your finger going over right side of surface. Volume is changed by going left and right, while pitch is changed by going up and down.
2) Derivative phrase, created from current scale, is repeated by tapping 8 pads on the left. Phrase is automatically changed by tilting body of iPhone or iPod Touch. It plays stable phrase by keep the face up. Or it plays high-tension phrase by keeping the face sideways.
3) Tilt it left and it speeds up, while it speeds down on tilting right.
You can change the key by tapping keyboards beneath.