In some aspects, a system is provided that includes a plurality of mobile devices and an application on at least a first mobile device. The application is adapted to track position information regarding the first mobile device, communicate the position information to a web server, receive position information from the web server regarding other mobile devices within a predetermined distance of the first mobile device, and use the position information regarding the other mobile devices to affect one or more characteristics of a video game executed on the first mobile device. Numerous other aspects are provided.