[jaminmc]

The reason why this works is because there is a magnet behind the screen right about where it shows the time when it is open. That is how the phone knows that it is closed, the sensor senses the magnet, and knows it is closed. When you bring in another magnet into the equation, it cancels it out and therefore changes the screen orientation.

Actually, most flip phones use magnets to sense if the phone is open or closed, (Well, Some use a little switch). Some laptops use magnets too for this. Like my macbook. If I stick a magnet by my "fn" key, it goes to sleep because it thinks it is closed. then I remove it, and it wakes up.