I really enjoyed learning about other tools for quick assessments to use before, during or after a lesson. The 2 I have posted on my blog above were very easy to use. I really like WallWisher. It's easy and fun to use, plus it's colorful. Students can also add photos to their sticky notes/comments.
These tools can be used in so many ways: KWL, exit ticket, quick short answer response, etc. You can use them for a quick grade and keep students accountable for their learning.
I probably won't use Today's Meet though b/c the students could abuse this by not putting their names and therefore posting silly or inappropriate comments.