INFORMATION TERMINAL, ON-BOARD INFORMATION SYSTEM, ON-BOARD DEVICE, AND INFORMATION TERMINAL PROGRAM

A portable information terminal that is connected to an in-vehicle device comprises: a first display unit; a display control unit that generates a first screen image for display upon the first display unit, and a second screen image for display upon a second display unit that is comprised in the in-vehicle device; and a screen image output unit that outputs the second screen image to the in-vehicle device.