This is cool technology. Basically you attach the iPhly actuator to your iPhone, down load the program, and then what you see is a visual slope indicator. By tipping the phone the plane responds with control movements. Holding the phone level makes the plane fly level. Moving your finger up and down the screen controls the throttle. 
Check their website out:
http://www.iphly.org/
More on this as I give my hands on one and give it a try.
