The app uses Google Transit to find alternative mass-transit options for your trips, and it gives you the option to instantly purchase offsets from your phone.

BBC: How big is your carbon footprint?

It has dozens of sub-products within it, from Google Transit (public transportation, e.g. subway, information and routing), Live Traffic, StreetView (and the incredible operation that makes that happen), Local search, image recognition technology for reading street and business signs, the list goes on and on.

FORBES: Why did Apple Fire the Maps Product Manager?

The app is missing some of the most useful features from the former iOS Maps app: Google's transit directions and street view images.

CNN: 5 big changes in iOS 6

Google's transit directions pulled in data from multiple services -- you could take a city bus to an unrelated train system traveling across state lines.

CNN: 5 big changes in iOS 6

Luckily, you can still access Google Maps from Safari to get the transit feature.

CNN: 5 big changes in iOS 6

In the lower left is a button that brings up your current location, and in the lower right is a tiny icon that lets you switch to satellite view, to see public transit and traffic information, or to launch the separate Google Earth app.

WSJ: Google Maps for iPhone Returns With Redesign That Makes It Easier to Use

Downloading all the transit apps still wouldn't be as useful as the Google version.

CNN: 5 big changes in iOS 6

Get comprehensive, accurate and easy-to-use maps with built-in Google local search, voice guided turn-by-turn navigation, public transit directions, Street View and more.

ENGADGET: Google Maps returns to iPhone, gives Apple users turn-by-turn navigation