As an American visiting Tokyo, Ive found this app to be indispensable for quickly & efficiently navigating the Tokyo rail systems. This definitely changed my life from the usual, old-fashioned method of staring at the subway map, trying to figure out how to get from point A to B. Now, I simply enter which station Im starting from, and which station Im going to, and voila… this app takes all the guess work out of the equation. Another plus is the fact that the map displays both in Romaji (English) and Japanese. So useful!