I simply cannot find a usage limit for this particular feature on google maps. I know for sure they have a complete documentation on usage limits like number of requests/map loads per day. But regarding drawing tools, I especially like polygons. How many points can you plot, how polygons can you draw?
Or at least in your common experiences, how many polygons drawn on a single map instance does it take till the application crashes or the map fails to load?
Google does not impose any usage restrictions on any of the overlays including polygons, markers, etc. I have used over hundred polygons on my map without any issue from Google. However depending on how many points are present in the polygon the application may crash. I had that issue when I was plotting a polygon with over 4000 points. A workaround is plotting the polygons when they are required.