This is a very welcome addition to my Haskell bookshelf. I bought the pdf version and it looks perfect on my ipad. I'm really glad to have the clickable version to have in a browser window as well. That seems a bit more convenient for finding stuff while coding.
I've been unable to put the ePub version of the book down on my iPad/iPhone. I was excited to have syntax highlighting and pagination. Excellent book so far. Highly recommend buying it.
I'm a little confused. Is there any ability to comment? I can see the comment toggle on the top right but nothing in the page. I've seen commenting in other O'Reilly books [1, 2] but not sure how it works with this one.
EDIT: Found this http://chimera.labs.oreilly.com/about and also realised I was getting the toggle the wrong way around. "Comments on" means they're on, not 'click to turn them on'. Then you click on a block of text to bring up a comment box.