How to measure the distance covered by iphone during free fall?

Question

During the free fall the iphone is supposed to send acceleration values as 0 on all the three axis. So how to detect the distance covered by the iphone?

Answer 1

From a standing start

distance = 0.5 x acceleration x time²

Gravitational acceleration = 9.81 m/s²

I'm going to assume you're not dropping the phone far enough to reach terminal velocity. If you do, I doubt your app will be of much use when you recover the phone :)