In-car information system, information terminal, and application execution method

An in-car information system includes a portable information terminal and an in-car device. The information terminal identifies a specific application being executed in the foreground and transmits restriction information pertaining to the particular application to the in-car device. The in-car device either allows or disallows, based upon the restriction information transmitted from the information terminal, image display corresponding to the application being executed in the foreground and transmission of operation information corresponding to an input operation.