A method of interacting with a television screen using a remote control having a viewing screen. The method includes the following: (1) displaying a boundary-identifier, on the viewing screen that is substantially transparent, to specify the boundary of a quadrilateral having a shape thereof dynamically depending upon at least one of the location of the viewing screen and the surface orientation of the viewing screen, wherein the surface orientation of the viewing screen is the orientation of the normal vector perpendicular to the viewing screen; and (2) detecting one or more positions being touched on the viewing screen after the boundary-identifier is displayed on the viewing screen.