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++.
* Add support for the SONY periodical format.
This means that news downloaded by calibre and sent to a newer SONY device (350/650/900) should appear in the Periodicals section and have the special periodicals navigation user interface
* Content server: Make the new browsing interface the default. The old interface can be accessed at /old
* Content server: Allow running of content server as a WSGI application within another server. Add tutorial for this to the User Manual.
* Support for the Pico Life reader, Kobo Wifi and HTC Aria
* Content server: Add a new --url-prefix command line option to ease the use of the server with a reverse proxy
* New social metadata plugin for Amazon that does not rely on AWS. Since Amazon broke AWS, it is recommended you upgrade to this version if you use metadata from Amazon
* Add a tweak to specify the fonts used when geenrating the default cover
* Add an output profile for generic Tablet devices
Closes tickets: 7289 [External link]
* SONY driver: Allow sorting of collections by arbitrary field via a new tweak.
* Content server: Make /mobile a little prettier
* Add button to 'Library Check' to automatically delete spurious files and folders
* FB2 Input: Lots of love. Handle stylesheets and style attributes. Make parsinf malformed FB2 files more robust.
Closes tickets: 7219 [External link] , 7230 [External link]
* Fix auto send of news to device with multiple calibre libraries. The fix means that if you have any pending news to be sent, it will be ignored after the update. Future news downloads will once again be automatically sent to the device.
* MOBI Output: Conversion of super/sub scripts now handles nested tags.
Closes tickets: 7264 [External link]
* Conversion pipeline: Fix parsing of XML encoding declarations.
Closes tickets: 7328 [External link]
* Pandigital (Kobo): Upload thumbnails to correct location
Closes tickets: 7165 [External link]
* Fix auto emailed news with non asci characters in title not being deliverd to Kindle
Closes tickets: 7322 [External link]
* Read metadata only after on import plugins have run when adding books to GUI
Closes tickets: 7245 [External link]
* Various fixes for bugs caused by non ascii temporary paths on windows with non UTF-8 filesystem encodings
Closes tickets: 7288 [External link]
* Various fixes/enhancements to SNB Output
* Allow Tag editor in edit metadata dialog to be used even if tags have been changed
Closes tickets: 7298 [External link]
* Fix crash on some OS X machines when Preferences->Conversion->Output is clicked
* MOBI indexing: Fix last entry missing sometimes
Closes tickets: 6595 [External link]
* Fix regression causing books to be deselected after sending to device
Closes tickets: 7271 [External link]
* Conversion pipeline: Fix rescaling of GIF images not working
Closes tickets: 7306 [External link]
* Update PDF metadata/conversion libraries in windows build
* Fix timezone bug when searching on date fields
Closes tickets: 7300 [External link]
* Fix regression that caused the viewr to crash if the main application is closed
Closes tickets: 7276 [External link]
* Fix bug causing a spurious metadata.opf file to be written at the root of the calibre library when adding books
* Use the same title casing algorithm in all places
* Fix bulk edit of dual state boolean custom columns
* Increase image size for comics in Kindle DX profile for better conversion of comics to PDF
* Fix restore db to not dies when conflicting custom columns are encountered and report conflicting columns errors. Fix exceptions when referencing invalid _index fields.
* Fix auto merge books not respecting article sort tweak
Closes tickets: 7147 [External link]
* Linux device drivers: Fix udisks based ejecting for devices with multiple nodes
* Linux device mounting: Mount the drive with the lowest kernel name as main memory
* Fix use of numeric fields in templates
* EPUB Input: Handle EPUB files with multiple OPF files.
Closes tickets: 7229 [External link]
* Setting EPUB metadata: Fix date format. Fix language being overwritten by und when unspecified. Fix empty ISBN identifier being created
* Fix cannot delete a Series listing from List view also dismiss fetch metadata dialog when no metadata found automatically
Closes tickets: 7221 [External link] , 7220 [External link]
* Content server: Handle switch library in GUI gracefully
* calibre-server: Use cherrypy implementation of --pidfile and --daemonize
New news sources
* Ming Pao by Eddie Lau
* lenta.ru by Nikolai Kotchetkov
* frazpc.pl by Tomasz Dlugosz
* Perfil and The Economic Collapse Blog by Darko Miletic
* STNN by Larry Chan
Improved news sources
* El Pais
* Fox News
* New Scientist
* The Economic Times of India