Google Play Books lets you search, preview, and buy millions of books using Google Book Search. Books in the public domain and certain copyrighted books can be read and downloaded in their entirety for free. You can buy ebooks for reading on your computer, Apple device, Android device, Nook, or Sony eReader in the Google ebookstore. All purchased eBooks are backed up online, and your page positions are automatically synced between devices.
- Only able to manage from the Google Play Books catalog. Cannot upload own books/documents. Does not sync with Kindle device, not able to edit metadata, &c.
- calibre is a ebook converter, not a store or reader