An observation: your 'feature box' shows two things that I can do (create & read; add notes & highlights), and one mildly techie thing (tablet optimized).

Concentrate on what people can do on your site and what problem it solves. To be blunt, I don't care if it's been optimized for tablets, phones, or Big Chief notebooks. I want to know why I should spend any more time on your site.

Also: the navbar and title take up a lot of vertical space. Use that space to show and tell me how you can make my life better.