If you mark up PDFs and use Microsoft Surface Tablets this might be a deal you want to look at. Drawboard PDF, a PDF mark up App is currently available in the Windows Store for “free.” The “free” price tag is listed in the Windows Store as “for a limited time only,” so I don’t know if this is a Black Friday promotion or not. Regardless, “free” is a deal worth noting.
Drawboard PDF is a mark up tool that you can use to edit PDF documents. Load in your PDF document and use a stylus with the radial menu to access a number of different mark up tools such as Strikeout, Highlight, Underline, or Squiggly to edit your documents. You can also insert text of shapes into a document, and there are a range of different pen widths and colors to choose from.
The makers of Drawboard PDF claim that you can do simultaneous Inking and drawing as you alternate between a stylus and your finger for navigation.
I’ve used Drawboard PDF on the Surface 2 to mark up a script and you don’t get to do much free form editing with that capacitive screen. Things are different on a Surface Pro 2 where Digital Inking is handled much differently. But regardless of which Surface you have, (or perhaps a Nokia 2520 or other Windows 8.1 Tablet) if you’re doing redlining, or highlight passages, Drawboard PDF might be a tool worth taking a look at. Especially, since for a limited time it is free.