What devices allow you to comfortably work with pdf, as with paper?

Question

Electronic books

There are many digitized books in pdf or djvu format, where you need to perform exercises on the principle of writing down the missing words with a pencil. Are there devices that allow you to do this comfortably or is there nothing better than a color printer yet?

Answer 1

An ordinary computer or laptop with Windows, a PDF file without protection and Adobe Reader - "Add text"
And write whatever you want anywhere on the page. Any font and any color.

Answer 2

If you have a graphics tablet, or a tablet computer with pen input, and use sane PDF viewers that allow you to insert handwritten comments, you can realize your desire. But it's still not very convenient, I checked.

Answer 3

Search applications by keywords pdf freehand annotation, there are many.
But you won't like it.