Since April 2018 the "share widget" found its way into 3d-webapps, so far so good.
Unfortunatly it does not have same funktionality as the share button in 3d-webSzenes, where the point of view is also shared as parameter in the link (&viewpoint=cam:13.75694499,51.03154795,124.18;23.989,83.874 , Im not sure if WebApps generally dont have option to put position parameters in the link).
Anyway, it would be nice if the viewpoint of a WebApp could also be shared, same way it works in WebScenes.