content: The reason for my one star is very simple. When using this app on the galaxy tab s4 I noticed when you jump from one section to the next using the bookmarks chapter 1 chapter 2 etc. The app completely freezes. After a while I noticed that if I instead of jumping around scrolled to the desired page this didnt happen. But when reading a pdf with 500 pages this is not convenient. It seems that the reader renders the pdf as you go along and if you say go to a other section and then back it completely forgets it already rendered that section. This is an easy fix not sure why it was implemented in this way in the first place. Will change review once fixed.