The next time you’re on the subway, or relaxing on a park bench or hanging out at a restaurant, take a look around and notice how people are interacting with their mobile devices. They are laser-focused on a single tiny screen at one time. Ask them how many apps they have open at one time – most likely, it's just one. They're not multi-tasking, they're single-tasking with a single screen while simultaneously beaming out their GPS location. If the "social" revolution that brought us Web 2.0 was all about Attention, then the new mobile revolution will be all about Location.