An interface/electronics module for reading information from a vehicle data bus and controlling functions available through the vehicle data bus. A graphical user interface is provided. The interface may include a stand-alone tablet computer or may be part of an integrated and permanently-mounted display. The interface/electronics module may include the functionality of the factory audio system (such as a radio tuner, power amplifier, etc.). In addition, the interface/electronics module is able to transmit commands via the vehicle's CAN bus.