I just found out about Skim and I find it to be wildly useful for personal use, but I can imagine this could be a huge productivity booster for anyone in academia in particular. In short, Skim views any PDF files quickly as expected, but more importantly it allows you to take notes and annotate sections of the PDF file itself, how cool is that? If you’re a student, teacher, researcher, educator, or anyone using PDF files regularly, you absolutely have to try out Skim and you will thank me later.

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Download Skim 1.2.2 now