Vehicular communication system, vehicular communication apparatus and portable terminal apparatus

A vehicular communication system comprising:

• a vehicular communication apparatus mounted on a vehicle;
• and
• a portable terminal apparatus communicably connected to the vehicular communication apparatus,
• wherein the vehicular communication apparatus includes:
• a vehicular storage device that stores a predetermined vehicular application for executing a predetermined function;
• and
• a vehicular input device that enters an operation for the predetermined function,
• wherein the portable terminal apparatus includes:
• a mobile storage device that stores a predetermined mobile application for executing the predetermined function, the predetermined mobile application providing a function for displaying a home screen, which includes a plurality of operation buttons for outputting the plurality of contents;
• a mobile input device that operates the plurality of operation buttons;
• an interoperation detection device that detects establishment of an interoperation state, in which the predetermined vehicular application and the predetermined mobile application interoperate with each other;
• and
• an operation input disable device that prevents the mobile input device from entering an operation for the operation buttons on the home screen when the interoperation detection device detects the establishment of the interoperation state.