Should you ever need a floor plan of your home, bringing in a professional to do the measurements might be expensive. And time consuming! So MagicPlan wants to replace human work, automatically creating a map of your humble abode.
Does it work? Sort of. The interface is a little wonky, and lining up the wall-measuring reticles with your camera is tricky. I managed to create a fairly accurate rendering of my kitchen, but my living room came out looking like it'd been sucked through a black hole. Still, the app is free, and allows you to (potentially) map out dozens of rooms in a multi-floored home, making things easier should you ever want to sell or renovate the place. One caveat: a creepy message about "anonymous data collection" pops up when you first start the app. With no explanation. Hm. [iTunes]