The Y Combinator Database - The definitive database of YC companies with all the metrics
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.
Startup School - How to start a startup, by Y Combinator
QGIS - QGIS is a desktop geographic information system, or GIS.
Apply to YC (Y Combinator) - Curated collection of resources for founders applying to YC.
OpenStreetMap - OpenStreetMap is a map of the world, created by people like you and free to use under an open license.