Ingress is an augmented reality game for Android and iOS developed by NianticLabs@Google.
Ingress is a massive multiplayer game in which two factions (the blue Resistant vs the green Enlightened) struggle for control over real-world territory, played by use of augmented reality. It was released on November 2012 on Android, and on July 2014 on iOS.
It required an invitation to play during the beta phase of the game. Now the game is still in beta, but is open for everbody