1. A computing device comprising: one or more processors; one or more computer-readable storage media storing instructions which, when executed by the one or more processors, implement a tracking system that includes a pairing service configured to perform operations comprising: receiving from a portable device, device acceleration gesture data associated with a series of motion gestures of the portable device; recognizing the series of motion gestures of the portable device; generating tracked object position gesture data associated with the series of motion gestures of the portable device; determining that the series of motion gestures of the portable device corresponds to the series of motion gestures recognized by the tracking system.