The best free PDF reader apps do more than just act as a PDF viewer - any modern browser can do that. What I'm looking for is tools that go beyond that, offering commenting, collaboration ...

There's no shortage of the best free ebook readers available for ... Despite its name, Sumatra PDF is a great little ebook reader, capable of displaying books in EPUB and MOBI format, as well ...

While PDFs can typically be reviewed in any PDF reader or editor ... In this case, it is best to use a designated free or premium PDF editor. PCWorld helps you navigate the PC ecosystem to ...