Android: Shake2MuteCalls is a lightweight Android application that turns motion — a sharp tap or a shake — into a physical kill switch for a loud ringer. It’s a great failsafe for those times you forget to silence your ringer.
Shake2Mute uses the accelerometer in your phone to sense when you’re tapping or shaking the phone and mutes the ringtone of the incoming call. You can adjust the sensitivity to suit your needs — and to keep just walking around from constantly muting your ringtone. When your phone rings, just shake it gently through your pants pocket or jostle your book bag, and the ringing mutes.