Okay, you all may think I'm crazy, or just another iPhone fanboy, but I think that the magnetometer, added to the current iPhone functionality, makes it well worth the early upgrade price. It's the most overlooked new feature, and it's definitely going to take this thing to the next level, and here's why: - The obvious reasons: use for navigation, such as in turn-by-turn software or as a simple directional guide. Heck, if it weren't for the battery requirements, this would make the iPhone a great survival tool. And hey, if you get one of those solar chargers for it, you even have that problem licked. - Even more advanced navigation. Imagine holding your iPhone up with the view from its camera on the display, and directions to a specific location overlaid on top of it. This will happen, along with other potential HUD-like applications. - Absolute Location: The magnetometer, combined with the accelerometer and GPS, allows the iPhone to determine its exact location and orientation in space. This allows for some very cool software possibilities, like an app that could label astronomical objects when you hold the phone up to the sky. - AR (Augmented Reality) games: We've all seen the video with the dog bouncing around on cards that have been laid on the ground, overlaid on the view from the iPhone's camera. Adding an accelerometer will make for even cooler possibilities, such as giving the iPhone the capacity to keep track of the locations of virtual objects no matter where they are with respect to the iPhone. The magnetometer is definitely going to enable some extremely cool possibilities for the iPhone in the very near future. Can you think of any that I haven't?