We knew Umihara Kawase Portable is basically a port of the PlayStation version with new stages. The updated official website has just revealed details of the new elements to be found in the unique looking platformer. They are the aforementioned new stages (on top of the original 50 stages), redone illustrations by artist of the original work Toshinobu Kondo and a “Replay” function for portability. Check out the updated website here, still no gameplay videos though.
Related: More Umihara Kawase Screens