A solid and indispensable app for Tokyo visitors

I find this app to be absolutely indispensable for navigating the Tokyo subway system. As an occasional visitor to Tokyo, the largest city in the world, I find that I cant get around without this app. The only small issue that you should be aware of is that the time estimates for travel between stations seem to be way too high. I find that I arrive at my destination in about half the time that is reported by the app.

cbseven about Tokyo Metro