This slide presentation gives several useful aspects to social gaming. It reviews statistical information on players and social game use. It notes patterns in game types and qualities. It gives an in depth analysis on how these noted qualities reveal game design. Most of the content is related to social networks that have nothing to do with proximity, but even so, the account is at the least a close cousin to my project. The similarities cross in different places in ways that are useful to my research.
Björk, S. (2010). Principles and patterns of social games: Where’s the difference compared to other games?. GCO Games Convention Online 2010. Leipzig.