A service providing system including an administrator terminal device, a user terminal device, and a service providing device. The service providing device authorizes a process to register a user terminal device after determining that the service providing device is connectable to both the user terminal device and the administrator terminal device via a wireless network. When the service providing device is under the care and supervision of the administrator, the service providing device is entrusted to register the user terminal device, thereby providing services to the user terminal device without burdening the administrator. The system further includes an image outputting device as one of service providing devices. The system adjusts a timing of producing an image, depending on who stays in a communication range.