Who still uses a paper folding map?
MapsWithMe, the extensive offline map, covers almost any country
in the world (be sure to download on beforehand if you don't want high internet costs abroad). No more fussing with paper maps that
never get folded back into their original position, and which outdate pretty quickly. Rather, download your maps and navigate through Japan zooming and scrolling around at will.
Since you cannot search for addresses or places with the lite version, the paid version is definitely worth the extra money. It also lets you bookmark places which is handy for retrieval.