public static synchronized void setTileProvider(final AbstractTileProvider newTileProvider) {
        if (newTileProvider != null /* && newTileProvider.isAvailable() */) {
            putString(R.string.pref_tileprovider, newTileProvider.getId());
            tileProvider = newTileProvider;
        }
    }
@return zoom used for the map of a single cache
main/src/main/java/cgeo/geocaching/settings/Settings.java