The device then periodically checks to see that it is still in the possession of its legitimate owner, by measuring the current stride and comparing it against that stored in its memory.More details over here.
If the phone suspects it has fallen into the wrong hands, it will prompt the user for a password if they attempt to make calls or access its memory.
Cell phone identifies owner by their walk
Posted on Monday, Oct 17 2005 @ 13:15 CEST by Thomas De Maesschalck
Scientists at the VTT Technical Research Centre of Finland have invented a new anti-theft feature for cell phones which uses motion sensors to record a user's walking pattern of movement.