NeighborDiff is a simple tool to update and detail geodata. We developed it to find changes a university made in their neighborhood in the 5 years since the local government collected a buildings file.

The building highlighted below was replaced by a parking lot. Drag and drop a red marker onto it to set it to Demolished.

The building under construction in the photo below is now a dormitory, and a journalism school is being built across the street. Drag and drop a green marker where new buildings should be added.

This building needs a name and description on the final map / export to OpenStreetMap. Click the building, add information, then click Save.

The output data can be added to OpenStreetMap with this site as proof of community review.

The buildings in NeighborDiff are stored on CartoDB. We use their Maps API to display and interact with the buildings, and their Node.js module + SQL API to change the status of buildings as you edit them.

CartoDB is a free/freemium mapping database from Vizzuality. You can upload shapefiles and Google Earth KML data to start creating a table.

Leaflet.js from Cloudmade, Wax from MapBox