I am looking for a PDF library organizer / tool. The requirements are:
I can create "shelves" where I could sort the PDFs by topics.
I could access it both from my iPad and from my Mac or maybe even the iPhone.
If possible (not necessary), there should be an easy way to annotate it on the iPad with the pen.
I never did find quite an organizer like this. I am looking to do it for school papers that I read.
Thank you.