The free, open-source Calibre is an e-book manager, e-book creator, and desktop e-book reader. It’s also a must-have tool for any bibliophile with an e-reader and a growing library. Calibre is compatible with devices from 15 e-reader manufacturers—including Amazon, Android, Apple, and Barnes & Noble—and the developers are quick to update the application when new e-readers are released.

Most e-readers automatically place you in their little ecosystems, with built-in book syncing, managing, and purchasing set-ups. Calibre steps in and gives the readers control over their libraries in a few ways. First, it manages your collection of e-books in a library that is sortable by author, series, format, and publisher, as well as other metadata. It’s also searchable by tags and comments. If your books are missing their covers or any metadata, Calibre will download the information from the Internet. The application can sync the library with your device when you connect to your computer. If syncing is too wired for your tastes, store your books on Calibre’s Web server and download them from any device with a browser and Internet connection.

The other half of Calibre’s powers are devoted to formatting content for your device. Converting common file types into the format supported by your e-reader is easy, and Calibre supports a large variety of both input and output formats. Want to read an HTML document on your Nook? Convert it with Calibre. Since reading isn’t a books-only activity, you can configure the application to format news in the best format for you device. It can even deliver full-length news articles from RSS feeds and publications like the New York Times, The Economist, and Macworld. Currently, Calibre is compatible with over 300 news outlets.

A final, unsung use for Calibre is as a desktop e-book reader. So far, mobile devices have monopolized the booming e-book market, with Apple going so far as to only make its iBookstore available to iOS devices. Calibre will open any e-book file in a clean, distraction-free window on your computer for an enjoyable reading experience outside of a mobile device.

The interface looks bright and user-friendly, but it can take some time to learn all of the many functions and menus. It’s understandable given the variety of tools this program is packing.

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