An on-vehicle device, which is connected to an external image taking device via the Internet so as to allow communication therebetween, includes a communication section, a reception notification section, a display section, a vehicle stopped state detection section, and a display control section. When the communication section receives an emergency (or call) detection notification from the image taking device, the display control section checks the vehicle stopped state detection section to determine whether or not a vehicle is stopped. If the vehicle is stopped, the display control section receives video data from the image taking device via the communication section for causing the display section to display a video image of the video data. Otherwise, the display control section notifies a user of an emergency (or call) detection notification via the reception notification section.