The following settings are found under the Menu tab (in green bar), Settings, Map.
Additional settings can be found under Menu tab (in green bar), Settings, Online maps.
Allow you to adjust how large the maps appear at each zoom level. This is especially useful when looking at open maps. Recommended default levels: Premium 100% / Online 200%.
Map cache size (MB)
To set the size of the map cache. When the cache is full, ViewRanger will throw away the oldest map tiles to make space. This setting is disregarded for Saved Maps.
Clear the online map map cache. All data is deleted. This setting is disregarded for Saved Maps.
Tile purchase buttons
When checked, zooming in on the map, will present buttons to download additional tiles adjacent to those you already own in that area. Tap to download and the credits will be debited from your account.
Map Promotion Button
Shows a icon in the top right of the map tab screen when additional premium mapping is available to buy.