The Pro version of Pocket Talkbox features the ability to change keys, up to two octaves higher or lower. This is an extreme advantage for musicians and recording artists. Turn your phone into a musical instrument from the future. Make the synth 'talk' just by holding the speaker to your mouth while you play. Shape the sound by moving your mouth. Now you can sound like Daft Punk, Stevie Wonder, Frampton and Zapp. The interface is simple enough for anyone to pick up and play, and intuitive enough for a true funk master to get down on. PRO TIP: Point the SPEAKER (not the MICROPHONE) into your mouth while you play the notes. Every musical instrument takes a certain amount of practice; this is one of them. Please try to understand how this instrument works before saying it doesn't. Have fun. For more info and a tutorial, please visit http://pockettalkbox.com.