A method of unlocking a second device using a first device is disclosed. The method can include: the first device pairing with the second device; establishing a trusted relationship with the second device; authenticating the first device using a device key; receiving a secret key from the second device; receiving a user input from an input/output device; and transmitting the received secret key to the second device to unlock the second device in response to receiving the user input, wherein establishing a trusted relationship with the second device comprises using a key generated from a hardware key associated with the first device to authenticate the device key.