Abstract: This invention further improves the operability of a mobile device by changing the operation screen of the mobile device in accordance with the operation status of the mobile device or that of an image forming apparatus in a communicable state when the mobile device and image forming apparatus become communicable with each other. When it is detected that the mobile device exists within a range of a predetermined short distance, status information is acquired from the mobile device to determine whether a file is selected in the operation screen of the mobile device. Information which designates an operation screen to be displayed on the mobile device is transmitted on the basis of the determination result.

Abstract: In a network system, a client device is connected to the network via a controller that enables a user of the client device to carry out a task using one or more services available on the network. The controller (10) has a service discoverer (12) that discovers services at locations on the network (N) and a task manager (14) that controls the carrying out of tasks using services discovered by the service discoverer (12). The controller (10) also has a service publisher (13) that, as a result of the discovery of a service by the service discoverer (12) makes that service discoverable by other controllers (10) connected to the network, thereby allowing those other controllers to discover and access that service or services via that controller.