Is the quality sufficent for classroom teaching? I use both for work as a teacher and I find Zoom much better than Hangouts. Zoom (when it works) is nearly flawless. Hangouts on the other hand has poor video, limited faciliation functions, limited grid/gallery view (and none at all on the iPad which is what my students use), random problems popping up, etc. Zoom is just much better for educaitonal use.