Have you heard of KIS? Keep It Simple, that's the idea behind the DC Metro Map application.
Features: * Full size map of the DC Metro system * Pinch zoom, scroll left and right on the map * Displays live real-time positions of trains (after map is left open for 15 sec) * Tap any train on the map to see its destination * Trip planner
No internet required for map. Internet required for live train positions and trip planner.