A display device includes a display; a memory storing at least one instruction; a communicator configured to communicate with a mobile device via a BLE communication network; and a controller including a processor configured to execute the at least one instruction stored in the memory. The processor is further configured to execute the at least one instruction to manage BLE identification information when the BLE identification information for identifying the mobile device connected via the BLE communication network is received from the mobile device during a normal mode in which an ambient service is being executed, and the communicator is further configured to, based on the BLE identification information received from the mobile device after a sleep mode is started, determine whether to wake up the controller based on whether information corresponding to the BLE identification information is stored in the communicator.