I primarily use large PDFs on the Mac Desktop version. When I open the same document on my iPad the page is not in sync with the page on the desktop version (and vice-versa). I know I can bookmark the page and the issue is resolved. However, it would be easier if the pages sync between the apps without the need to use the bookmark feature. I hope that makes sense! Otherwise, I love this app! I actually tell people it is worth get an iPad JUST for this app!