A method of tracking a lead mobile device , the method comprising: receiving , at a user mobile device that is tracking the lead mobile device, tracking data that includes a current location for both the lead mobile device and at least one other mobile device that is also tracking the lead mobile device, wherein the receiving of the tracking data is based on: automatically activating a tracking of the lead mobile device by the at least one other mobile device when a short-range wireless connection between the at least one other mobile device and the lead mobile device is lost, and automatically deactivating the tracking when the short-range wireless connection between the at least one other mobile device and the lead mobile device is regained, such that tracking for specific followers is activated and deactivated as the distance between the lead mobile device and its followers varies; displaying , at the user mobile device, the current locations of the lead mobile device and of the at least one other mobile device that is also receiving the tracking data, wherein displaying the tracking data comprises graphically displaying on a map the current locations of the lead mobile device and of other mobile devices that are tracking the lead mobile device and wherein displaying the current locations of the lead mobile device and of other mobile devices comprises visually distinguishing the lead mobile device from the other mobile devices and also visually distinguishing the user mobile device from other mobile devices that are also tracking the lead mobile device; and receiving, at the user mobile device, user input to select a new mobile device as the lead mobile device. receiving , at a user mobile device that is tracking the lead mobile device, tracking data that includes a current location for both the lead mobile device and at least one other mobile device that is also tracking the lead mobile device, wherein the receiving of the tracking data is based on: automatically activating a tracking of the lead mobile device by the at least one other mobile device when a short-range wireless connection between the at least one other mobile device and the lead mobile device is lost, and automatically deactivating the tracking when the short-range wireless connection between the at least one other mobile device and the lead mobile device is regained, such that tracking for specific followers is activated and deactivated as the distance between the lead mobile device and its followers varies; displaying , at the user mobile device, the current locations of the lead mobile device and of the at least one other mobile device that is also receiving the tracking data, wherein displaying the tracking data comprises graphically displaying on a map the current locations of the lead mobile device and of other mobile devices that are tracking the lead mobile device and wherein displaying the current locations of the lead mobile device and of other mobile devices comprises visually distinguishing the lead mobile device from the other mobile devices and also visually distinguishing the user mobile device from other mobile devices that are also tracking the lead mobile device; and receiving, at the user mobile device, user input to select a new mobile device as the lead mobile device. <EOS>