An ePUB file is essentially an archive of HTML files. So why not read ePub-files with a program which is specialized in displaying HTML files and many people have already installed? That's the idea which lead to the creation of EPUBReader as a Firefox addon. It runs on every platform Firefox does (Windows, MacOS X, Linux) and now on mobile devices.
If you click on a link to an ePub-file, you are normally prompted by the Firefox "save as" dialog. With EPUBReader installed, the ePub-file is downloaded, processed and directly displayed ready to read.
EPUBReader consists of two parts. There is the reader application and a simple ePUB library manager. The manager gets installed as a bookmark entry in your list of bookmarks. It is called ePUB Library.
Added in 1.2.2/3
- ePub-files opened with EPUBReader can now be saved to a location of choice. Just click on the disk button at the bottom or on the library-page.
- Focus is now set to the ePub content page, so you can now start immediately paging through the epub page using spacebar or page up/down keys.
Added in version 1.2.4.
- Now it's possible to set a bookmark in an ePub-file. An ePub-file opens automatically at the position of the bookmark.
- EPUBReader adds now a margin to each ePub-file.
- Margins and background-color of the ePub-content can now be changed via the preferences window. When you change the background-color, please reload your ePub-files. Otherwise the background-color of the TOC on the left side will be changed too.
Added in 1.2.5
- Downloaded ePub-files open now in a new tab or in the already opened EPUBReader-tab.
- Every unique ePub is now added only once to the ePub-Library. This works for every ePub which has been added with version 1.2.5.
- Font-color of the ePub-content can now be changed via the preferences window.
- Fault tolerance has been further improved. Now there are even less ePub-files which can't be read.
- EPUBReader is now multilingual. As first German translation has been added.
Added at 1.2.6
- Support for OPDS catalogs has been added. As first Feedbooks.com and Archive.org (1.5 Million books) catalogs are available. If you use Calibre2Opds, you can also add your Calibre catalog. Go to the EPUBReader preferences window, tab "Miscellaneous" and enter the URL of your catalog.
- EPUBReader is now available in five additional languages: Greek, Spanish, French, Lithuanian, Portuguese. Some words are still in English because I made some changes recently. Chinese is missing completely because I have some problems with the Chinese characters . I'll contact those who made translations with more information.
- When ePub-files are saved via the EPUBReader "Save"-buttons, they get now more meaningful names (title, author). This works with all epub-files which are loaded with version 1.2.6.
- The ePub-Library (which is now called "ePub-Catalog") opens now in a new tab.
- The font-size of the ePub-content can now be changed on the "Content" tab of the preferences dialog.
Added at 1.2.7
- EPUBReader is now available in six additional languages: Dutch, Hebrew, Italian, Polish, Russian, Simplified Chinese.
- The font of the ePub-content can now be changed in the preferences.
- DRM protected ePub-files are now detected. Instead of a general error message a dedicated message is shown.
- In many cases (e.g. server requires authentication) are now dedicated messages shown instead of a general error message.
- OPDS-feed of Beam-eBooks.de has been added.
- OPDS-feed with links to DRM free ePub-websites has been added.
- Seamonkey-support has been added.
Added at 1.2.8
- Bugfix: On some websites automatic download didn't work.
- EPUBReader is now available in seven additional languages: Finnish, Swedish, Esperanto, Hungarian, Danish, Brazilian Portuguese and Japanese.
- Now it's possible to export ePub-files from the private library or import them into the private library. Click on the circle at the top of the private library.
- Now it's possible to keep your private library in sync with the content of a defined directory. Combined with a sync tool like Dropbox, you can easily read your ePub-files on different computers. Click on the circle at the top of the private library.
- The content of the private library can now be sorted by clicking on the headers.
- In the private library is now the date displayed at which the ePub-file was added.
- The font of the table of contents can now be changed.
- Font-face, font-color and background-color which are defined in an ePub-file are now displayed correctly.
- If you really want to download an ePUB file rather than read it hold down the shift key while clicking the link. On some sites that are .php pages you may need to right click and select "Save link target as" to download the file. The 1.2.2 version now has a Save command while viewing the file or on the ePUB library page to save the viewed file somewhere else.
- If you accidentally remove your library bookmark you can add it back in. Type chrome://epubreader/content/index.html. into the URL line to access it and then save this location as a bookmark.
- If you access an ePUB book using a URL or file access the entry will be placed automatically in the ePUB Library for later reading. You should always access it subsequent times from within the Library Manager to avoid duplicate entries. (There is a delete button in the Library Manager to remove these duplicates.)
 How it works
It downloads an ePub and then expands in into its various files automatically and then reads the resultant XHTML files using the browser itself. It is all done totally transparently. EPUBReader adds the buttons and menu items itself.