Georgia Tech's OMSCS master's degree program used to use Udacity for all of its lecture videos. I personally liked Udacity. A couple years ago, Georgia Tech moved everything to their own platform on Canvas. I heard there were issues with it not being easy to make updates to videos on Udacity. Plus, the Udacity app never supported Georgia Tech logins like the website did, and it was a pain to view videos on mobile devices. I'm not sure of the exact reason for the move though, since it may have been a business decision.