I want to store my PDFs, iBooks purchased from Apple, and epub's that I purchased from other sources in one place that allows me to organize and search them, and hopefully sync them between my two Macs and my iPhone and iPad. I believe that iBooks cannot do that. I do not see syncing in the iBooks app. If iBooks doesn't do this I believe I would like to store my reading material in Dropbox and use a third party app to manage and read my apps. I read MOSTLY on the Mac, so that is most important to me. Any suggestions for a very good reader for PDFs and ePubs?