Windows only: Freeware application PDF-XChange Viewer is a quick PDF reader that lets you perform all kinds of useful PDF editing tasks. Among all of the features (and it is rich with them), ...

Switch from Adobe Acrobat to Okular, a fast, free PDF reader with powerful annotation tools, no ads, no subscriptions, and support for multiple file formats.

Free PDF viewer with unique UI in terms of flat design and original layout. Annotate PDF with a complete set of tools, manage PDF files, connect to cloud services and even protect PDF with signature.

Windows: Want to create PDF files from plain documents, annotate and fill in existing PDFs, extract images, and leave notes for any PDF reader? Nitro PDF Reader does all that, and it's a free download ...