From Kovid Goyal
A one stop solution to all your e-book needs. It is free, open source and cross-platform in design and works well on Linux, OS X and Windows. calibre is meant to be a complete e-library solution and thus includes library management, format conversion, news feeds to ebook conversion, as well as e-book reader sync features and an integrated e-book viewer.
I come from the Unix world, which means calibre is architected in little pieces each with its own command line interface which means that each piece of functionality is reusable not just in python programs but in any software. In fact adding complete support for converting any new ebook format to calibre requires the writing of only two converters format->html and html->format as well as a metadata reading/writing tool. All the other features of calibre will work automatically with these three converters in place. Similarly, writing a device driver requires very little work. You basically have to implement a well-defined interface (interface.py). Once you do that, your device will have full support in calibre.
Adding support for new Input/Output formats
Calibre is written primarily in Python with a few C extension modules. So you have to contribute plugins in either Python or C/C++.
* Device drivers for the: Teclast K-5, Samsung SNE-60 and Samsung i7500
* When showing cover browser in a separate window, remember the last used window size
* Add keyboard shortcuts to show/hide the Tag Browser, Book details and Cover Browser panels. Hover your mouse over the buttons that toggle them to see the shortcuts.
* Calibre library: When the case of title or author is changed, automatically rename the folders to reflect the new case, even on case insensitive filesystems
* Metadata download: If downloaded title or author is all upper case, automatically fix the case
* Add method to add books by ISBN. Click the arrow next to Add Books to add from a list of ISBNs.
* Allow editing of tweaks via Preferences->Advanced
* Add button to the manage authors dialog to automatically reset all author sort values
* Fix regression in 0.7.13 that broke changing libraries
* MOBI Output: When processing an input document that specifies non-existant files in the OPF guide, don't crash.
* E-book viewer: When opening consecutive documents in the same viewer, show the correct title in the titlebar
* Set screen size to 540x718 in Kobo output profile
* Dont allow calibredb to create custom columns with invalid labels.
* Fix preference to 'search as you type' not working
* iTunes driver: Fixed bug in PDF file name searching after adding to iTunes database (Windows only)
* Displaying HTML comments: Do not start a new paragraph at the period in words like Ph.D
* Respect restriction in effect when refreshing book list
* Fix drives being reversed for softrooted nook