In this technical note about a recent eBook that I created, I wrote about the need to include a hyperlink (back to the page where you came from), on the target page. It seems that this is no longer necessary with an ePUB inside the iBooks app on the iPad/iPhone.
Why? Because in version 1.2 of iBooks, it seems that a history of the navigation pathway is kept while the eBook is open. This is then utilised to display (at the bottom of the page) a 'back to page x' hyperlink, when the navigation items are showing*.
Maybe all the talk of ereading devices just reinforces an artificial barrier to entry. Maybe you should be able to get to your bookshelf from any computer anywhere, without software. Maybe DRM is just an occasional password prompt. Maybe there’s no such thing as an ebook file. Maybe there’s nothing to download. Maybe the best ereader is the one you have with you.
Although the DRM-free EPUB files in our ebook bundles are compatible with many reading systems for print disabled customers, many readers prefer the DAISY format that Bookshare provides, and either don't qualify for access via Bookshare, or would prefer to pay for the ebooks. Through a collaboration with Bookshare, today we've started making DAISY files available within our ebook bundles on oreilly.com ...
Mike Rankin from InDesignSecrets.com has made some neat little apps using AppleScript for zipping and unzipping ePub, Docx, Indl, and Fla files on Mac computers. These file types are based on the zip file, so they can easily be zipped open with an archive utility (just change the file extension to .zip).