I use Okular for that. It's open-source and present on three major platforms. I really got surprised to find out how feature-rich it is. It has a lot of basic/i

I use Okular for that. It's open-source and present on three major platforms. I really got surprised to find out how feature-rich it is. It has a lot of basic/important features - like highlighting, underlining, strike through, inline notes, pop-up notes, freehand line drawing, inserting shapes (like arrow, rectangle, polygon) etc. Tip: you actually don't need to install kde toolkit to be able to run Okular on Windows and macOS. Search for nightly builds - I'm on a nightly build and it's pretty solid.