A subset of geofences is selected from a set of geofences operating in an area, each geofence in the subset satisfying a primary consideration relative to at least one other geofence in the subset. In response to a first payload of a first geofence and a second payload of a second geofence satisfying a secondary consideration, a combined geofence definition is formed by combining a first definition of the first geofence with a second definition of the second geofence. At a data processing system distinct from a mobile device traveling in the area, the first payload is combined with the second payload to form a combined payload. The combined geofence definition and the combined payload are transmitted to the mobile device.