I’m trying both the print and PDF versions to see if I notice different things, which would make sense, as the reading experience is different.
And if the reading experience is different, does that suggest that the meaning is different?
And if the meaning is different, does that suggest that the device makes the meaning?
The best PDF annotating tool is Acrobat Pro, which is not free, but has a 30-day free trial.
There are also some free options.