With Calibre you can convert your books to multiple formats, and then sync with all of your devices. KEY FEATURES INCLUDE Library management. Calibre keeps things orderly by creating single entries for books, which contain multiple formats. Calibre also adds tags and comments for better searching. Format conversion. Calibres varied conversion options give you support for a wide variety of file formats. File syncing. Calibres device drivers will support all of the top devices and e-readers.