: A free version for viewing, signing, and annotating PDFs. Open-Source/Free Tools : LibreOffice Draw : Can perform basic PDF text editing.

: Adobe now offers Acrobat Pro via a Creative Cloud subscription, ensuring you have the latest security features and AI-driven tools.

: Patched versions frequently crash or lack full functionality compared to official software.

: Robust online tools for merging, splitting, and converting documents. Okular : A free, feature-rich document viewer and annotator.

: Since it no longer receives security patches, it is highly susceptible to modern exploits. Modern Alternatives

If you need to edit or manage PDF files, consider these safer options:

: Adobe Acrobat XI is an outdated version of the software. It reached End of Support on October 15, 2017. Adobe no longer provides security updates, bug fixes, or technical support for this version.