Cesium tagged stories
Cesium has introduced full support for glTF models. A demo with example aircraft, ground vehicle, and character models is available. There is also a tutorial on how to use the Cesium API for glTF, and a tool to convert COLLADA to glTF (based on COLLADA2GLTF).
The COLLADA to glTF converter online tool allows you to convert your COLLADA models to glTF for use with Cesium. Simply drag-and-drop your COLLADA file (.dae) and any images it references by zipping them together. A self-contained glTF file will be downloaded once the conversion is finished, and a model preview will be shown below.