A system comprising an electronic device and a communication device, the electronic device comprising: a near field communication unit that is configured to perform wireless communication with the communication device; a display comprising a display screen; and a processor, wherein the processor is configured to perform operations including: performing a plurality of functions of processing data; setting a function restriction mode in which at least one function of the plurality of functions is restricted, according to an operation by a user of the electronic device; while the function restriction mode is set, displaying data input by an uoperation by the user of the electronic device, on the display; detecting whether a communication connection with the communication device by the near field communication unit is established; and if it is detected that the communication connection between the near field communication unit and the communication device is established, for a predetermined period switching the display screen to a screen representing that the function restriction mode is set, and after the predetermined period elapses, while keeping the function restriction mode to be set, switching the display screen and returning to the display screen displayed before the communication connection has been established between the near field communication unit and the communication device, and displaying on the display, the data input by the operation by the user of the electronic device thereby enabling the user of the electronic device to continue inputting data; and wherein the communication device is configured to receive function restriction mode data stored in the electronic device and enabling a user of the communication device to check whether the function restriction mode has been set in the electronic device on the basis of a screen of the communication device displayed on the basis of the function restriction mode data. a near field communication unit that is configured to perform wireless communication with the communication device; a display comprising a display screen; and a processor, wherein the processor is configured to perform operations including: performing a plurality of functions of processing data; setting a function restriction mode in which at least one function of the plurality of functions is restricted, according to an operation by a user of the electronic device; while the function restriction mode is set, displaying data input by an uoperation by the user of the electronic device, on the display; detecting whether a communication connection with the communication device by the near field communication unit is established; and if it is detected that the communication connection between the near field communication unit and the communication device is established, for a predetermined period switching the display screen to a screen representing that the function restriction mode is set, and performing a plurality of functions of processing data; setting a function restriction mode in which at least one function of the plurality of functions is restricted, according to an operation by a user of the electronic device; while the function restriction mode is set, displaying data input by an uoperation by the user of the electronic device, on the display; detecting whether a communication connection with the communication device by the near field communication unit is established; and if it is detected that the communication connection between the near field communication unit and the communication device is established, for a predetermined period switching the display screen to a screen representing that the function restriction mode is set, and after the predetermined period elapses, while keeping the function restriction mode to be set, switching the display screen and returning to the display screen displayed before the communication connection has been established between the near field communication unit and the communication device, and displaying on the display, the data input by the operation by the user of the electronic device thereby enabling the user of the electronic device to continue inputting data; and wherein the communication device is configured to receive function restriction mode data stored in the electronic device and enabling a user of the communication device to check whether the function restriction mode has been set in the electronic device on the basis of a screen of the communication device displayed on the basis of the function restriction mode data.