Method and apparatus for interacting with a display screen. A remote control comprises a viewing screen. The method includes determining the boundary of a quadrilateral on the viewing screen having a shape thereof depending upon at least one of the location of the viewing screen and the surface orientation of the viewing screen. The method also includes the following: displaying a boundary-identifier to specify the boundary of said quadrilateral on the viewing screen that is substantially transparent; detecting one or more positions being touched on the viewing screen; and determining at least one mapped position on the display screen under a mapping operative to map said quadrilateral on the viewing screen to a rectangular on the display screen under a prospective transform.