TerriaJS
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npm install terriajs
TerriaJS is a library for building rich, web-based geospatial data explorers. It uses Cesium for a full 3D experience. Think Google Earth, except it runs in a web browser, without a plugin. It also uses Leaflet for a basic 2D experience on systems that can't run Cesium.
A live demo of an application built on TerriaJS can be found here:
Australia's National Map
Instructions for incorporating TerriaJS into your application are coming soon. In the meantime, see the GitHub repo for Australia's National Map for an example.