The app consist from 2 parts: • polygon GPS registrator • area and perimeter calculator The registrator takes a polygon vertices coordinates through the mobile GPS-receiver and if GPS signal deviation is not out of accuracy setup restriction then it registering a vertex. The next vertex is registering when the distance from the last fixed vertex also exceeding the user defined distance threshold i.e. step. For the polygon area measurement required at least 3 registered vertices. The app also me