The MapQuest Android Sample Code by MapQuest demonstrates code to access basic map view, basic satellite view, latitude/longitude, polygone, location, and traffic. Enterprise key is required to interact with the API. An unofficial sample is available at https://github.com/sebasira/Android-RouteWebService
Developers with their own geographic imagery will soon be able to publish it as a layer on the Google Maps API and Google Earth API. Dubbed Google Earth Builder, the service will launch in the third quarter. From the looks of the announcement here at Where 2.0 conference, Google is dipping its toe into the traditional GIS industry. The maps developers upload will be available via API, but only to enterprise customers who pay Google for geo services.