If you're the sort to tear down your Galaxy S III, you might have noticed a mysterious STMicroelectronics LSP331AP chip lurking on the motherboard. While we've known that it's a pressure sensor, we now know that it's a new generation -- new enough that ST is just getting to explaining the technology to a mainstream audience. The piezoresistor-equipped MEMS chip tracks altitude through atmospheric pressure with an uncanny knack for precision; it can tell when you've crossing between floors, which could be more than handy for future iterations of indoor navigation. Don't worry if you're an extreme sports junkie that might push the limits, either. The sensor can do its job at the kinds of pressure you'd normally see when 32,800 feet high or 5,900 feet below sea level, which should keep it working even if you're checking your phone during a climb up K2 or a HALO skydive. We don't know if anyone beyond Samsung is lined up to use ST's pressure sensor in their devices, but we wouldn't be surprised if it becomes a mainstay for smartphones and outdoor gear in the near future.