There's a new reader I found on XDA that is being developed called Fabrik. The developer is still adding features, but it is already quite usable. One of the greatest features compared to all the other Android readers is its integration with Dropbox. It uses dropbox to store books, as well as reading information for those books, including syncing your location for reading in the books.
There are other android reader apps that have an extra app to sync (to dropbox or otherwise), but this is the first one I've found that syncs automatically and without an extra app.
give it a shot: