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So I couldn't find this on our site so far, but I recently downloaded this app on my ipad. This program essentially allows you to mark up PDFs, articles, etc. by highlighting, taking notes, and so forth. It runs around $9.99, so I was a little hesitant at first, but this app is really valuable! I've always struggled to read articles paperless, and this app really helped by productivity levels skyrocket. You can also export your notes, so you can basically write your papers/etc. as you read.