First off, awesome. I've always wanted something like this (especially for pg's essays) and kicked around ideas for how to build something like it. A few bits o

First off, awesome. I've always wanted something like this (especially for pg's essays) and kicked around ideas for how to build something like it. A few bits of feedback, mostly on the design/interaction side: I don't think only offering twitter sign in is ideal, the pagination was not very intuitive/easily discover-able (horizontal might be ok in mobile context with swipes, but on desktop people want to scroll), the function of the bottom progress bar is also not intuitive to me (seems more like a zoom at first glance), the content itself is a little too "boxed in"- don't think there is a need to contain it like that, and lastly the mobile experience (Gnex) is lacking (everything is quite small, ui nearly impossible to interact with). Totally understand that this is just a demo and you've probably thought of this stuff already but thought I'd chime in just in case it is useful. Great work!