GeoTiff Maps and other raster files, which contain a coordinate reference system can be visualized with this app.
In addition to various raster formats, there is also support for the MBTiles format.
The app queries the Android media store for existing appropriate files and presents a list of results. If your desired file is not found, you can browse to it manually.
Your can determine your position on the map if it is covered by the file.
The app is limited to display files up to 10 MB. To view larger files, the functionality must be purchased.