This well-designed and easy-to-use free PDF viewer lets you mark up and create PDFs. Adobe’s popular PDF format makes files look great and Adobe’s free Reader lets everyone look at the files for free.

PDF-XChange Editor is has a boatload of features, for creating, editing, annotating, and securing PDF documents. The fully functional free versions offer plenty for many users, but you’ll have to pay ...

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, and ...