A non-transitory computer readable storage medium is provided. The non-transitory computer readable storage medium has stored therein instructions, which when executed by a mobile device, cause the mobile device to: provide, at a processing circuit, a signal to a transmitting electrode of a first touch panel; transmit, at the transmitting electrode, the signal to a receiving electrode of a second touch panel of a computing device; and perform further operation with the computing device when the signal corresponds to a signature stored in the computing device.