ipadGo here for the instructions for iBookstore >>

With iBooks for iOS, you can view PDFs or E-Pub files on your iPhone, iPad, and iPod Touch. You can also read iBooks on your Mac computer. The iBooks system can read PDF and E-Pub files.

How to get a new book onto your Nook (or Kobo)

Go here for the instructions for Nook or Kobo >>

The E-Pub format is the most broadly available and supported format worldwide. Here’s a useful set of instructions on how to import and install E-Pub files as books on your Barnes & Noble Nook or Kobo e-reader (available at many independent bookstores).