Launches Google Maps with a particular mode and location/destination.
Exactly one of Address or Lat/Long must be specified. Address is not valid for StreetView mode.
Address is in the format X+Y+Z e.g. Littleton+Delaware
Zoom is only possible with Point / StreetView and a Lat/Long specification.
Label is only possible with Point mode, it will show a marker with the specified label.
Google Maps version 3.2.1 or higher is (probably) required for Navigation.