A gaming server periodically receives location information from a plurality of distributed gaming devices. Such devices can take the form of cellular telephones or other wireless communications devices equipped with a GPS transceiver. When the gaming server determines that a gaming device is within a predetermined range of another gaming device, it sends an authorization message such as an "in-range" message to one or both of the devices within range of each other. The users of the device(s) receiving the in-range message are then authorized to "shoot" the other user, e.g., by taking a picture of them, pointing a laser at them or other gaming action that may be specified by the rules of the game. The gaming action could also be initiating a game.