A head mounted display, HMD, device, comprising: a communication processor configured to communicate with a mobile terminal comprising a touch screen; a display configured to display a content received from the mobile terminal; and a controller configured to: in response to an event generated on the mobile terminal, display an object on the display corresponding to the event generated on the mobile terminal, based on a type of the displayed content, wherein the controller is further configured to: differently control a display position of the object corresponding to the event, based on at least one of an execution time of the displayed content at the time of the event occurrence, so that when the execution time of the displayed content at the time of the event occurrence has not exceeded a reference time, the object corresponding to the event is displayed on a preset region of the display, and when the execution time of the displayed content at the time of the event occurrence has exceeded a reference time, the object corresponding to the event is alternatively displayed on an edge region of the display; and in response to a first touch gesture applied to the touch screen of the mobile terminal or an elapse of a predetermined time while displaying the object corresponding to the event, remove the object from the displayed content. a communication processor configured to communicate with a mobile terminal comprising a touch screen; a display configured to display a content received from the mobile terminal; and a controller configured to: in response to an event generated on the mobile terminal, display an object on the display corresponding to the event generated on the mobile terminal, based on a type of the displayed content, wherein the controller is further configured to: differently control a display position of the object corresponding to the event, based on at least one of an execution time of the displayed content at the time of the event occurrence, so that when the execution time of the displayed content at the time of the event occurrence has not exceeded a reference time, the object corresponding to the event is displayed on a preset region of the display, and when the execution time of the displayed content at the time of the event occurrence has exceeded a reference time, the object corresponding to the event is alternatively displayed on an edge region of the display; and in response to a first touch gesture applied to the touch screen of the mobile terminal or an elapse of a predetermined time while displaying the object corresponding to the event, remove the object from the displayed content. in response to an event generated on the mobile terminal, display an object on the display corresponding to the event generated on the mobile terminal, based on a type of the displayed content, wherein the controller is further configured to: differently control a display position of the object corresponding to the event, based on at least one of an execution time of the displayed content at the time of the event occurrence, so that when the execution time of the displayed content at the time of the event occurrence has not exceeded a reference time, the object corresponding to the event is displayed on a preset region of the display, and when the execution time of the displayed content at the time of the event occurrence has exceeded a reference time, the object corresponding to the event is alternatively displayed on an edge region of the display; and in response to a first touch gesture applied to the touch screen of the mobile terminal or an elapse of a predetermined time while displaying the object corresponding to the event, remove the object from the displayed content.