Control music playback without taking the iPhone or iPod out of your pocket. Just gently hit on the pocket to skip tracks. - Hit twice: skip to next track. - Hit three times: skip to previous track. It works great in any pocket or bag, no matter if you are walking or running. Just adjust the sensitivity slider to suit the level of body activity. - Plays music from iTunes library. - hit2skip app must be active to enable the 'hit' control gestures. ***** This free version of 'hit2skip' is supported by iAds. You may purchase the full version to disable any ads. ***** NOTE: The device may not be locked for this app to work properly. hit2skip requires the accelerometer. Locking the device disables the accelerometer. Do not hit too hard. Hitting the device hard may lead to injuries and/or damage of the device.