Subway riders can now see when their train is coming before going underground.

MTA Subway Time is now available on all smartphones via mobile web.

The latest technological feature from the Metropolitan Transportation Authority gives straphangers real-time arrival estimates on the 1 through 6 lines and the 42nd Street Shuttle.

It's similar to the countdown clocks seen at stations along these lines.

Those who have iPhones can also download the Subway Time app from the Apple app store.