Ingress is an augmented reality game that I play.  Unlike most people I play solo.  Back when I started you had to get an invite from a player to play, or request an invite from the game.  I overheard some people talking about it in a restaurant and asked the game for an invite, and mine came about 2 weeks later.  I never used any of the invites I was awarded by the game.

The main crux of ingress is basically going to public places of interest and claiming them for your team, or damaging the claim on it made by the opposing team.  I am part of the Resistance (blue team) opposed to the Enlightened (green team).  These places of interest are called portals in the game, and Ingress has had a system of identifying new spots for portals and editing portals that are inaccurate.  I noticed that many of the "info" fields about these places have been left blank, which is a shame, since part of the game is finding these things in your community.  I think I'm going to put some effort into researching some of  the local portals and getting some of the information about them shared.