In the present specification, a digital device and a method of processing data in said digital device are disclosed. Here, a digital device according to an embodiment of the present invention comprises: a memory; a user interface unit that receives a menu request signal through a remote application executed in an external device; a display unit that displays an executed application; and a control unit that determines the properties of the received menu request signal on the basis of the application being displayed and generates menu data, implements controlling to transmit the generated menu data to the external device and output the menu data through a screen of the external device, and when a menu item selection signal of the menu output from the external device is received, implements controlling to transmit or activate menu data corresponding to the menu item selection signal.