Kaizena From Google

I was perusing through some on-line articles this evening and I came across information on a very cool program.  It's call Kaizena and you access it through your Google account.  Forgive me if you know about this-I did not.  This program is basically a super cool way to give students feedback on their work.
How many hours have you spent hunched over a stack of assignments, pen in hand thinking to yourself that you have spent an enormous amount of time sitting at your desk that you will never get back?  Well, I dare say that this might actually save time, and you might actually enjoy giving students feedback.  With this program you can add voice memos, and videos as feedback devices for your students.  You can also save your resources so that if you see the same error in several assignments, you can access your resources from the program, and don't need to re-open or return to a different window to do it.  I would imagine that students would be able to use the program themselves in the same way and assess their own work. I am just dying to try this out!
Below is a brief video tutorial for how to use the program.  The tutorial is an example of how you might use it in a secondary setting, but I know it's applicable in elementary and middle years as well.
I'd love to hear your thoughts on how you would use this program in your own class.