Thanks to the built-in compass in the iPhone 3GS, it is now possible to turn your iPhone into a magnetic field and metal detector.
With this video, you can get a sneak peek of our new iPhone application that detects items such as keys, money, and personal electronics with the traditional sounds and display of a metal detector. It can also be used as a theremin (the instrument popularised by the Doctor Who theme) if you have a fridge magnet or two handy!
Magnetic Flux & Metal Detector will be available on the App Store shortly. You can find out more details at http://philandben.com/