A couple years ago Parallel Mafia MMORPG (Free)
This is one of the first location-based games that I played and is a lot of fun. Parallel Mafia is based in the future, where criminal organizations run wild. Your job is to control your turf, take over other players’ areas and stop the Apex Agency. The virtual world the game creates is superimposed on a map of your GPS location. To be able to travel in the game you need to know a real person in that location or physically travel there and turn on the game.
When you begin, you will need to complete the tutorial. During this time, you will build your safe house and a few business fronts. It is at these businesses where you earn experience, build your influence, find items, and fight off computer-generated bad guys. To grow your character, you need to craft items and raise your skills (called augments), plus spend in-game credits. Now, you earn these in-game credits by referring friends to the game or via in-game purchases. The game has an extensive chat system in place to allow you to add friends.
Overall, these are fun games but not quick ones. These are games you can play a little each day and where ever you are, the game is with you. You can play alone or with others. Location based games add a nice dimension to games and I would assume more will be developed over the coming years.