@nhinkle I didn't know that. Thank you!

@Breakthrough Thank you. What you have just written is partly a valid answer to my question. (I still find it a little rude that you and few other people preferred to close the question instead of telling me just what you have written.)

@Breakthrough If there is no automated way to zoom into the actual text in PDF, it is still a valid answer for me. On the other hand, since this simple Onyx Boox thing I have is partly open source, I though that maybe its functionality made it through to the PC world already.

@Breakthrough By this logic one should close every question, once it gets a single accepted answer.

@Breakthrough I'm afraid it is not that easy. Many ebooks have different margins for odd and even pages. And even then, for someone who reads tons of different PDFs, manually adjusting the zoom isn't really a good option.

@Daniel Thank you. Do you think I should re-post the question again with the proper wording, or just leave it closed as it is now?

OK. I basically changed "PDF reader" -> "way to read PDF files".

@DanielBeck I understand. But that's silly, isn't it? The rewording doesn't change the actual meaning, just the vocabulary I use (to avoid words like "program" or "reader")