Method, apparatus and navigation apparatus for sharing display by plural operating systems

A display apparatus where results of processing by a plurality of OSs are displayed on a same display unit, comprising:

• a memory which expands said processing results in correspondence with said plurality of OSs,
• a display environment changer which changes, in correspondence with said plurality of OSs, display environments to be set for expanding said processing results,
• a display superimposer which displays a plurality of frames in a state of being superimposed on each other, said plurality of frames being expanded into said memory, and
• an input device which receives a user input, wherein, as to one display area on a display unit at which said plurality of frames are superimposed, said input device determines further display areas, within said one display area utilized by said plurality of OSs, with reference to a position on said display unit at which said user input is performed and a superimposing mode of said plurality of frames, and transfers an input event of said user input to one of said OSs which displays at said position, wherein said input device determines, in correspondence with a background of said superimposed display, said OS to which said input event is to be transferred.