Okular is a universal document viewer based developed by KDE. Okular works on multiple platforms, including but not limited to Linux, Windows, Mac OS X, *BSD, etc. Okular combines the excellent functionalities with the versatility of supporting different kind of documents, like PDF, Postscript, DjVu, CHM, XPS, ePub and others. Okular is a Free Software PDF reader.
- Okular can not manage e-book readers. It's only a glorified document reader.