You could avantgo or plucker this:

http://www.nycsubway.org/maps/route/

It is the old style of drawing the map. This is how they used to do it before they became more fancy (more accurate?) with the newer maps.

Or, try tube from http://www.visualit.co.uk/palm_tubenyc.htm# (they have other maps.

I'm not sure I want to pay $30 (or 21 for the non pro) for the pro version, but playing with the free non pro version is a hoot.

It does two things metro (which i love) doesn't, show you the stops between the stop you start and get off at. always helpful if you going someplace new. It also shows you on a map the route. super cool.

The databases you load can go on the SD card, but it seems slow in loading.

Not sure the extra benefits are worth the money compared to the free Metro program.

But it is a cool app.