A new game is fascinating gamers around the world: In Ingress, Google developers combine geocaching with augmented reality. It's played not on a home computer, but outdoors on a smartphone.
Players have to go from one location to the next with their mobile devices. In the game, real cultural landmarks become portals that have to be claimed. Ingress works exclusively online with permanently enabled GPS. It allows Google to gather valuable GPS data as a byproduct.