On mobile (KitKat, Chrome) the actual annotations obscured the text, and I couldn't figure out how to actually see them. It was easy to scroll through the unannotated bits though.
Thanks for the heads up. We definitely designed primarily for desktop use (where most people probably read legal docs), but definitely should do something for mobile as well. For the time being, we may just hide the annotations on small screens so it doesn't obscure the reading process (and then come up with a more elegant solution later).