I am looking for an application (something like DEVONthink or StickyBrain, but they don't seem to have this feature) that allows me to store, organize, and most importantly annotate PDFs. When I say annotate, I mean the ability to add comments to sections of text in a similar manner to MS Word's comment feature (within its Track Changes capability).
Does there exist such a piece of software? Or do I have to just harass DEVON and Chronos to get them to add this feature?