iMetro provides you with multiple subway maps for metro cities over the world!

I recently moved to New York City and was completely clueless about getting around this place. Thankfully for this iMetro app, I was able to navigate the subway lines.

This app compiles subway maps from metro cities all over the world such as London, NYC, Toronto, etc..
I quite like the usability as well, single click to zoom in/out and drag to pan the map.
Dislikes: No possible way to go back to chose another map. You have to quit the app and start over.

Note: Make sure to install this to the memory card, since it takes up over 15 Mb.

Download here.