The Dink Network

It could be a similar problem I had with key presses in Pilgrim's Quest - it seems key presses on iPhone would happen happen twice with one press, although that may not account for what you're experiencing. In PQ it was the F key which was a "toggle" key press, one press and Frog mode was activated, next press it was de-activated, so with the one press being read as two by the iPhone version of the engine Frog mode was activated and de-activated each time.

Robj wrote some clever code to get around this for me.