May I recommend in the spirit of being a paper-like experience that you include the option for a simulated page turn. Also, in PDF documents a view option that suppresses margins so that the text is as close in size to a full-sized piece of paper. Seeing the entire page of text is helpful to remembering the key points of the texts. But shrinking the page make it difficult to read. While most readers also zooming in on text in PDF, the big flaw is the zoom either requires undesired scrolling and doesn’t stick when flipping to the next page.