A mobile equipment (ME) for tracking an event comprises at least one storage device; and at least one processing circuit, coupled to the at least one storage device. The at least one storage device stores instructions, and the at least one processing circuit is configured to execute the instructions of: activating a digital tag of the event in the ME, to track the event; and generating an indication on the ME according to the digital tag, when a distance between a first position of the ME and a second position at which the event occurs is greater than a threshold.