Is it possible to change the browsing or reading mode to scroll mode instead of navigating with arrows?
This is not possible from what I can see. You can also go back and forth by double tapping the left and right edges of the screen. As you may know already, you can tap and drag down when highlighting the last sentence in order to see the rest of the setence. However I find this slow and annoying; it would be nice if there was an auto-scroll behaviour when tapping or selecting the last sentence to make things faster and smoother.