This field stores a geographic features on the map, allowing paths (linestring) and boundaries (polygon) to be drawn on the map and to be saved.
To make this possible, you must export the profile Cartograf.
In one of the Trackers of the profile Cartograf in this case the Tracker Zones connected to the Tracker Map through the field Map of the Item Link type, you can see the field Zone of the Geographic Feature type. It is through this field that you can, once the profile has been exported, draw the paths and boundaries on a map that you would have created.
As you can see from the capture below, the Tracker Zones has a field of type Geographic Feature called Zone.
So, very simply you can customize your maps by adding paths and boundaries using the field type Geographic Feature.