Calibre Portable is the standalone version of the popular ebook manager, Calibre – a powerful, feature-rich tool to keep your ebook collection perfectly organized. Like its desktop counterpart, Calibre Portable is a library for eBooks. It has a big, bold interface that's really easy to use, and ebook files of most formats can just be dragged into the Calibre Portable window. Editing the metadata (title, genre, etc.) is just a case of hitting the button on the toolbar and typing in your changes. Calibre Portable lets you select multiple books and edit them in bulk too, for example, if you want to regroup some books in a particular genre.
Viewing is also just a button click, and opens an ebook reader window. Here you can increase or decrease the font size to your comfort, add bookmarks, and more. You can also set Calibre Portable to download feed from news websites, although the layout results are sometimes a bit odd. There is also, of course, ebook reader synchronizing, so you can easily keep your device up to date. Free, open-source, easy to use, and with no installation, Calibre Portable is a great e-book library tool and reader.