E-books in ePub format can be viewed on virtually any device. But when giant e-book retailers want you only reading books on their devices, true ePub format becomes difficult to find. As of 2015, Amazon, one of the largest book retailers, only offers e-books in mobi format, and Barnes & Noble offers an altered form of ePub — meaning its e-book downloads only can be viewed on a Nook.
Kobo
Kobo is an online retailer with a wide selection of e-books available in ePub format. Titles include fiction and nonfiction, and the company has a library of nearly 4 million e-books to browse, which includes "The New York Times" best sellers and indie offerings. Chances are that new book everyone is raving about is available on this site, so grab it and read it on the device of your choice.
Harlequin
If you want some spice in your ePub read, browse the selection of risque romance novels at Harlequin.com. This publishing company specializes in the genre and puts out more than 110 titles each month. Its romance sub-genres range from historical and religious to intrigue, so you're sure to find what you're looking for, and all of the e-books come in ePub format.
Google Play Books
Google Play Books has titles from best sellers and indie authors, much like Kobo. Just select and purchase your desired title and follow Google’s “download and transfer books to eReaders” instructions. There is an option to download your purchase in ePub format.
Your Local Library
You can borrow e-books from your local library’s website. Your library’s online catalog most likely is filled with ePub- and PDF-format e-books since there is no assumption as to what reading device you are using. Go to your library’s website and search for an “e-books” link. You’ll need a library-card number to borrow the books.
Project Gutenberg
Project Gutenberg started as an effort to digitize works of cultural importance and grew into a large digital library that offers all its titles in ePub format. The site is an ePub paradise with more than 46,000 free e-books from which to choose. Most of the titles are in the public domain, which means there are plenty of classics in the catalog.