Samsung Electronics today unveiled a new mobile phone featuring an optical joystick, which the 
company believes may change the way users interact their handsets. Users manipulate the optical joystick key by placing their finger and moving a cursor to navigate through menus, similar to a mouse cursor on a PC.
Optical sensors will read and react to users’ finger movement, thus breaking down the traditional four-way menu navigation and providing 360 degrees of freedom. DailyTech - Samsung Unveils Phone With Optical Joystick