Described is a system and method by which an auxiliary computing device having an auxiliary display platform that displays information corresponding to data that originated on the main computer system may be extended by a device manufacturer. Extended hardware is added to the device, such as a radio receiver and/or an audio decoder. The auxiliary display platform is layered and extensible at each layer, and includes an extensible hardware abstraction layer that is extensible to support extended hardware if needed, and a driver layer that is extensible by adding driver code for the extended hardware. A runtime layer is also extensible to support the extended hardware as needed, as are libraries, the auxiliary shell program and other managed code. The client API is also extensible to allow applications on the main computer system to communicate with extended hardware via the device runtime layer.