You can now download the free widget for ArcOnline web apps.    Want a quick overview : here’s a movie :

All features of 3D Mapping Cloud now become instantly available within every ArcOnline project :
– fuse complex 3D Mapping data
– unlimited volumes and sizes of point clouds
– blend data together from different 3D content providers
– combine views such as spherical street-level imager and 3D point cloud
– perfect integration in ArcOnline : view location, content extent, search for content, etc..
– measure in 3D content
– add annotations and 3D Models (see image with this blog post)
– and much, much more…

The widget is added in the Web AppBuilder application to instantly create ArcOnline web apps. This widget is based on the standard 3D Mapping Viewer SDK, using the JS API. The implementation is open source: anyone (i.e. any developer) can download and rebuild, or adapt to your needs. Check out the Developer Zone for more information.