I can't read anything offline, nor access my archives with the app (either in Chrome or on the iPad). Apparently I have too many books.
If you can get into Read Now (which takes accessing the full Kindle store and Manage My Kindle), it does work. But, what a pain.
OK, I guess, if I don't have the book downloaded in the Kindle IPad app (but, why not download it, if I have wifi access, anyway) or want to look at something quick on the PC (again, have to go thru the Manage My Kindle page, as there is no 'read now' on the book page and the archives are blocked). Somewhat useful (if a pain) there, since I don't have Kindle for PC on this computer (then again, that's because I don't read on it).