Foxit
One of the best tools for making comments and keeping notes while you read the PDF is the FOXIT PDF Reader.
There are lots of dhamma books as in scanned documents converted to PDF or as in text based PDFs. When we read these books we want to keep notes about the areas we would like to revisit, bring up as a question for a dhamma discussion, or to remember. There are many different PDF readers out there but one of the best readers which is free and also carry many different useful commenting features is Foxit – you can download Foxit from their website below: