New York City Subway Map for iphone from Playback Media
New York City Subway Map is a free application for iPhones that provides access to subway maps and information for New York City subways.
The application is available offline for the New York City, New Jersey, and Long Island areas of the US. It provides the live status of each line in real-time, so you know if a delay is to be expected. You can also see your current location on a map, and also the stations near your current location.
In addition, it provides a route finder, which you can use to plan your journey and get all the information that you need about each station.