Google Maps
If you need to rely on public transportation, there isn’t a better app than Google Maps. It has all the Phoenix area public transportation information uploaded into their database.
The app will detect your location and give you directions to the place you’re trying to go, either by foot or by various public transportation.
They’ll tell you when to leave to head to the latest stop, what trains or buses to take in which direction, and give you an estimate of how long it will take for you to get there.
You can’t find an app that makes using transportation in an unfamiliar city any easier.
Google Maps is available in both iTunes and Google Play store.