A method for rendering application user interfaces on a television screen executes at a computer system coupled with the television screen. The computer system includes one or more processors and memory storing a plurality of applications configured for execution by the one or more processors. The method provides a user interface of a first application of the plurality of applications for display on the television screen. The method receives from a personal user device a user interface of a second application. The personal user device is distinct from the computer system and the user interface of the second application is provided by one or more programs executing on the personal user device. The method concurrently displays on the television screen the user interface of the first application and the user interface of the second application.