EDpuzzle is similar to Educanon and Zaption. It allows you to add comments and questions to videos that you use for instruction. You can also crop the videos, which I think is really awesome. To demonstrate, I used a very short video of my two Westies, Bucco and Sadie, at the beach last Sunday.
One thing I really like about EDpuzzle is that your students can create their own video projects and save them to the class, although in our district we are, of course, limited by the blocking of YouTube.
EDpuzzle is also available on the iPad and iPhone.