One curmudgeon's reaction ...<p>I'm sure it's wonderful. I use MarkDown to take notes, I link them together, and I use Spaced Repetition systems to learn and review. Having everything linked together in a single system is potentially interesting and useful. This looks like exactly the sort of thing I am primed and ready to use.<p>It says "Start Learning for Free", and then I need to sign in with an email and password, or with Google.<p>Without knowing more about it, how it works, where things are stored, what it does differently from everything else, what your privacy policies are, whether I can import/export data, and without actually trying it, I'm not signing up.<p>Closed.