Tile Sources

You can use following sources of map tiles:

Source	Code	Sample	Terms
OpenStreetMap Mapnik tiles	mapView.getLayers().setBaseLayer(new TMSMapLayer(new EPSG3857(), 0, 20, 0, "http://a.tile.openstreetmap.org/", "/", ".png"));		Free for limited use. See tile usage policy.
MapBox Streets	mapView.getLayers().setBaseLayer(new MapBoxMapLayer(new EPSG3857(), 0, 19, 333, "nutiteq", "map-j6a1wkx0"));		MapBox Terms & Feedback. Please create your map to use own account and map IDs.
MapBox Satellite	mapView.getLayers().setBaseLayer(new MapBoxMapLayer(new EPSG3857(), 0, 19, 334, "nutiteq", "map-f0sfyluv"));		MapBox Terms & Feedback. Please create your map to use own account and map IDs.
MapQuest Open Tiles	mapView.getLayers().setBaseLayer(new TMSMapLayer(new EPSG3857(), 0, 20, 1, "http://otile1.mqcdn.com/tiles/1.0.0/osm/", "/", ".png"));		Free. Please place “Tiles Courtesy of MapQuest ” on your page, or in the copyright area of the map and link the word “MapQuest” to http://www.mapquest.com.
MapQuest Open Aerial	mapView.getLayers().setBaseLayer(new TMSMapLayer(new EPSG3857(), 0, 11, 1, "http://otile1.mqcdn.com/tiles/1.0.0/sat/", "/", ".png"));		Free, but limited number of zooms. Please place “Tiles Courtesy of MapQuest ” on your page, or in the copyright area of the map and link the word “MapQuest” to http://www.mapquest.com.
Microsoft Bing Maps	mapView.getLayers().setBaseLayer(new QuadKeyLayer(this.proj, 0, 19, 4, "http://ecn.t3.tiles.virtualearth.net/tiles/r",".png?g=1&mkt=en-US&shading=hill&n=z"));		Commercial terms of Bing Maps API. Must use Get Imagery Metadata Bing Service to get supported URL parameters.
Microsoft Bing Aerials	mapView.getLayers().setBaseLayer(new QuadKeyLayer(this.proj, 0, 19, 5, "http://ecn.t3.tiles.virtualearth.net/tiles/a",".jpeg?g=1&mkt=en-US"));		Commercial terms of Bing Maps API. Must use Get Imagery Metadata Bing Service to get supported URL parameters.

References

• OSM Wiki TMS page