Described is a system and method including an auxiliary display platform having an interface (API) set that provides a way for client applications running on a main computer system to interact with various types of auxiliary displays, irrespective of differences between various device implementations. Interaction includes displaying content and notifications provided by the application, and returning events to the application. In one implementation the API set comprises a set of COM objects that register and perform configuration checks of a client application, send content and notifications to attached devices, and return events from the attached devices. The application may send data to an endpoint corresponding to a communication destination (e.g., a particular auxiliary device application) and a contract (e.g., a format) for the data. The platform and API set thus provide an abstraction layer for applications to provide information independent of any particular auxiliary device implementation.