Sync not consistent, added file using desktop but app wont sync it, even though synced online. Seems to have added ability to remove PDF file from phone/iPad once youve read it, but APP CRASHES when I try to delete a pdf. Would like ability to highlight, select and copy text from within app. Glad it is presently free, if functionality is improved would be worth paying for, but for now, not worth it. Oh, and it crashes randomly & frequently - closing the program, leaving you trying to figure out where you left off. Great concept, and good that I can read files offline, but a hassle to use.