A mobile terminal includes a wireless communication unit; a camera; a display; an ultrasound transmission unit; and a controller configured to control the wireless communication unit, the camera, the display, and the ultrasound transmission unit. The mobile terminal is configured to: transmit a first detection prepare request signal to allow a plurality of external devices located within a control area to switch to a prepare state; acquire an image including at least one of the plurality of external devices that switches to the prepare state; selectively transmit an ultrasound signal to the at least one of the plurality of external devices included in the image; receive associated control information from each of the at least one of the plurality of external devices; and display a graphic image related to the associated control information from each of the at least one of the plurality of external devices.