A system and method are described for location-based and group-based operations on a data processing device. For example, a computer-implemented method according to one embodiment of the invention comprises: establishing a group containing identities of a plurality of users within the group and notification data indicating when other users are to be notified about current locations of the users in the group; determining whether wireless data processing devices of two or more users of the group are at the same location or within a particular distance of the location; identifying the users and the location; and notifying other users in the group of the identity of the users and the location.