US Patent 8736438 Computing device as a vehicle key

In general, this disclosure discloses techniques for using a computing device as a smart vehicle key. The computing device may send a validation request signal to a vehicle via a first short-range communication protocol. After to sending the validation request signal, the computing device may establish a secure connection with the vehicle over a second short-range communication protocol. The computing device may send via the secure connection an ignition signal to the vehicle that activates an ignition system operable to activate a motor of the vehicle. The computing device may periodically send via the secure connection a keep-alive message to the vehicle as the motor of the vehicle is running.