I recently bought a Nexus 7 thinking it would be a more versatile option than the Kindle ereader I was using, but as I was reading a Krishna book (I have interest in religion) I noticed letters that have uncommon accent marks just appear as black squares. I am not sure if this is the app or if the Nexus doesn't have the appropriate character set or not. (The words appear correct on the actual device) I have enclosed a screen cap.