—The success of Web 2.0 communities demonstrates that the users of an information service are willing to participate in the content creation process on a voluntary basis. In this paper we adapt this idea to the task of collecting geographic data by player communities of location-based games. We identify three types of geographic data that players can collect as part of the game experience: (1) data about the localization/communication network, (2) data about the geographic environment, and (3) related non-geographic information. Furthermore, we present game design patterns that permit to gather all three types of data. The approach is illustrated with the Geogame “CityExplorer”. First empirical results are reported from the evaluation of geographic data acquired over a one-year period with two Geogames, “GeoTicTacToe” and “CityPoker”.