An air-conditioning remote controller (10, 110, 210) configured to operate an air-conditioning apparatus, the air-conditioning remote controller comprising: a display unit configured to display various information, an image acquisition processing unit configured to acquire image data from an external communication terminal, a display processing unit (52B, 152B, 252B) configured to display, on the display unit, a settings management screen for operating the air-conditioning apparatus, and the image data acquired by the image acquisition processing unit from the communication terminal, characterized by further comprising a memory unit configured to store a display switching table, the display switching table associating a plurality of pieces of the image data with a plurality of the settings management screens, wherein the display processing unit (52B, 152B, 252B) is configured to select, in response to a transition of the settings management screen, the image data corresponding to the settings management screen from the display switching table, and displays the selected image data on the display unit, wherein the display processing unit (52B, 152B, 252B) has a function of switching between modes, the modes including an air-conditioning management mode that displays the settings management screen on the display unit, and a standby mode that hides the settings management screen in accordance with a setting or an operation, and wherein the memory unit is configured to store a plurality of the image data associated with the standby mode, and wherein when switching to the standby mode in accordance with a setting or an operation, the display processing unit (52B, 152B, 252B) is configured to erase the settings management screen from the display unit and then display one of the plurality of the image data associated with the standby mode, and display another one of the plurality of the image data associated with the standby mode in a superimposed manner over a portion of the one of the plurality of the image data; wherein the air-conditioning remote controller (10, 110, 210) further comprises an image settings processing unit being configured to make, as a display setting, a multi-image display setting that simultaneously displays the plurality of pieces of the image data, and execute a setting that, in a manner superimposed over a piece of image data to be displayed on the entire screen of the display unit, displays another piece of image data or other pieces of image data on a portion of the display unit. a display unit configured to display various information, an image acquisition processing unit configured to acquire image data from an external communication terminal, a display processing unit (52B, 152B, 252B) configured to display, on the display unit, a settings management screen for operating the air-conditioning apparatus, and the image data acquired by the image acquisition processing unit from the communication terminal, characterized by further comprising a memory unit configured to store a display switching table, the display switching table associating a plurality of pieces of the image data with a plurality of the settings management screens, wherein the display processing unit (52B, 152B, 252B) is configured to select, in response to a transition of the settings management screen, the image data corresponding to the settings management screen from the display switching table, and displays the selected image data on the display unit, wherein the display processing unit (52B, 152B, 252B) has a function of switching between modes, the modes including an air-conditioning management mode that displays the settings management screen on the display unit, and a standby mode that hides the settings management screen in accordance with a setting or an operation, and wherein the memory unit is configured to store a plurality of the image data associated with the standby mode, and wherein when switching to the standby mode in accordance with a setting or an operation, the display processing unit (52B, 152B, 252B) is configured to erase the settings management screen from the display unit and then display one of the plurality of the image data associated with the standby mode, and display another one of the plurality of the image data associated with the standby mode in a superimposed manner over a portion of the one of the plurality of the image data; wherein the air-conditioning remote controller (10, 110, 210) further comprises an image settings processing unit being configured to make, as a display setting, a multi-image display setting that simultaneously displays the plurality of pieces of the image data, and execute a setting that, in a manner superimposed over a piece of image data to be displayed on the entire screen of the display unit, displays another piece of image data or other pieces of image data on a portion of the display unit.