YC-backed Glassmap is a new mobile application publicly launching today that presents a viable challenge to realtime, location-sharing apps like Apple’s Find My Friends or Google Latitude. Where those two competitors focus on enabling social experiences on top of their own platforms or ecosystems, Glassmap is enabling a third alternative: realtime location tracking built on top of Facebook’s social graph. Yes, it’s like a “Find My Facebook Friends.”
However, this app isn’t using Facebook check-ins to track your friends – it’s actually tracking them in real time, by running the app passively in the background. And that’s where Glassmap’s killer feature comes in: the startup is using “relay” technology to minimize the typical battery drains associated with realtime location-sharing apps today.