Cross-posted from the Thumbtack engineering blog. I recently released an open-source mapping toolkit called Rotary Maps that helps you make realtime maps on top of Google Maps v2 or v3. It also supports making maps in a simple DOM element if you don’t care for Google Maps. Check out the full post at the Thumbtack [...]
The most recent release of Cartographer.js supports county-level choropleth maps. This was the number one requested feature for Cartographer and I am delighted to finally be able to offer it in an official package. Counties are stored with efficient polygon encoding, and are easily referenced by name.