Thanks for the feedback, we're definitely going to add some more screenshots. In the mean time we've updated our landing page with a short introduction video (which was also already posted in the comments here).
We're looking to trigger feedback when it's still fresh in the users' minds (i.e, after you just left a meeting), thus the focus on mobile; but we put a lot of effort into our web-app as well, and see that some users prefer to use only that.