We take our mobile phones everywhere we go, and it’s become scary easy for services and apps to collect information about our movements. But there are limits to what these technologies can do; they work best outdoors. Our guests in our first season finale episode, Yan Shvartzshnaider of NYU and Colleen Josephson, a doctoral student at Stanford, recently wrote a fascinating piece for Princeton's blog, Freedom To Tinker, about how a new technology embedded in the most recent generation of Apple iPhones, has the technology to track the owner's movements, down to the inch, indoors.