To provide an "on-vehicle device" which enables a user to utilize an application provided in a portable terminal while the user is troubled by useless operations as little as possible.

The on-vehicle device includes: application list display control means (S12) for making a display part display a list of application identification information for specifying an application executable in a portable terminal; terminal application execution control means (S14) for, when one piece of application identification information is selected from the list of the application identification information displayed at the display part, making the portable terminal activate and execute the application specified by the selected application identification information; application normal execution determination means (S15, S18) for determining whether or not the application is to be normally executed; and terminal application re-execution control means (S14) for, when it is determined that the application is not to be normally executed, making the portable terminal reactivate and execute the application.