A display apparatus comprising: a display; a memory configured to store at least one instruction; a communicator comprising communication circuitry configured to communicate with a mobile device via at least one wireless network; and a controller including at least one processor configured to execute at least one instruction stored in the memory, wherein the at least one instruction, when executed by the at least one processor, controls the display apparatus to: start execution of a predetermined application which is an application for displaying a content image on the display; during execution of the predetermined application after the execution of the predetermined application is started, perform a first scan operation to identify, through the communicator, whether a registered mobile device which was previously paired with the display apparatus is present; in response to the registered mobile device not being identified as present via the first scan operation, maintain the execution of the predetermined application; after a time period from when the first scan operation is performed, perform a second scan operation to identify, through the communicator, whether the registered mobile device is present; in response to the registered mobile device not being identified as present via the second scan operation, maintain the execution of the predetermined application; and in response to the registered mobile device being identified as present via the second scan operation: maintain the execution of the predetermined application, and control a process to be started to automatically end the execution of the predetermined application based on a result of a third scan operation being performed subsequent to the second scan operation. a display; a memory configured to store at least one instruction; a communicator comprising communication circuitry configured to communicate with a mobile device via at least one wireless network; and a controller including at least one processor configured to execute at least one instruction stored in the memory, wherein the at least one instruction, when executed by the at least one processor, controls the display apparatus to: start execution of a predetermined application which is an application for displaying a content image on the display; during execution of the predetermined application after the execution of the predetermined application is started, perform a first scan operation to identify, through the communicator, whether a registered mobile device which was previously paired with the display apparatus is present; in response to the registered mobile device not being identified as present via the first scan operation, maintain the execution of the predetermined application; after a time period from when the first scan operation is performed, perform a second scan operation to identify, through the communicator, whether the registered mobile device is present; in response to the registered mobile device not being identified as present via the second scan operation, maintain the execution of the predetermined application; and in response to the registered mobile device being identified as present via the second scan operation: maintain the execution of the predetermined application, and control a process to be started to automatically end the execution of the predetermined application based on a result of a third scan operation being performed subsequent to the second scan operation. start execution of a predetermined application which is an application for displaying a content image on the display; during execution of the predetermined application after the execution of the predetermined application is started, perform a first scan operation to identify, through the communicator, whether a registered mobile device which was previously paired with the display apparatus is present; in response to the registered mobile device not being identified as present via the first scan operation, maintain the execution of the predetermined application; after a time period from when the first scan operation is performed, perform a second scan operation to identify, through the communicator, whether the registered mobile device is present; in response to the registered mobile device not being identified as present via the second scan operation, maintain the execution of the predetermined application; and in response to the registered mobile device being identified as present via the second scan operation: maintain the execution of the predetermined application, and control a process to be started to automatically end the execution of the predetermined application based on a result of a third scan operation being performed subsequent to the second scan operation. maintain the execution of the predetermined application, and control a process to be started to automatically end the execution of the predetermined application based on a result of a third scan operation being performed subsequent to the second scan operation.