@golgaloth

There are some FOSS PDF tools out there, but they tend to be fairly single-purpose, whereas Acrobat is more of a Swiss Army knife of PDFs.

Consider:

* Viewing, printing, annotating PDFs: Evince, Okular, or your favorite browser

* Rearranging PDF pages: PDF Arranger https://github.com/pdfarranger/pdfarranger

* Scanning to PDF: GNOME Document Scanner, aka simple-scan https://github.com/GNOME/simple-scan

* Editing the entire PDF as vector graphics: LibreOffice Draw & Inkscape