Best app for travelling in New York city

[Salil]

Hello Friends,

I would like to know the best IPhone app to use to travel in New York City and from NYC to New Jersey. I was wondering if there was a app that would use my current GPS location and after asking for my destination in New Jersey would map out a plan for me by considering bus, walk, train and subway to get to my destination. And of course it must take into consideration my current time as well.