Mapbox - An open source mapping platform for custom designed maps. Our APIs and SDKs are the building blocks to integrate location into any mobile or web app.
Duolingo - Duolingo is a free language learning app for iOS, Windows and Android devices. The app makes learning a new language fun by breaking learning into small lessons where you can earn points and move up through the levels. Read more about Duolingo.
QGIS - QGIS is a desktop geographic information system, or GIS.
LanguageBeast.com - Study English synonyms and antonyms to enrich your vocabulary
OpenStreetMap - OpenStreetMap is a map of the world, created by people like you and free to use under an open license.
Babble - A more personalized social network