When your Android device is connected to the Internet, the application loads the tiles corresponding to the map visible on the screen. These tiles are stored in a database and can be reused later. They will be reused if they are new or when your device is no longer connected to the Internet. The app keeps up to 600 MB of tiles in the directory of your choice.
By default, except for the United States, the application starts loading “OpenStreetMap Mapnik” maps.
You have the choice between
- Default (OpenStreetMap Mapnik)
- Bing
- Bing satellite
- MapBox satellite
- NOAA marine
To switch from one type of card to another, press the layer button 
at the top right of the screen.