For years I was extremely interested in an e-Ink tablet for reading scientific papers, but while the technology and hardware became more and more available, I realized that there is no scenario that such hardware would ship with software able to properly annotate PDF documents in an interchangeable format (like valid PDFs f.E.). And that this would be stable and supported for some reasonable time.
Source: My experience with Android tablets, iOS and Linux PDF-Software and every presentation of eInk-tablets seen so far, where this is never really part of their pitch.
Source: My experience with Android tablets, iOS and Linux PDF-Software and every presentation of eInk-tablets seen so far, where this is never really part of their pitch.