Does anyone know of an app that allows you to annotate directly on the pages of an etextbook that you have purchased? I have noteability for annotating PDF's, however, most etexts are not in PDF form. I want to be able to annotate the etext just as if I were annotating a PDF. Does an app like this even exist? Tried searching, came up with nothing. If this has been covered, please link me in the right direction!