I guess ebooks annotation is hard to export, copy and sync. Journal files store in "/sdcard/.edge/.esi-content/" if you add it in library. Library database store in "/sdcard/.edge/.esi-data/". If you don't know how to use SQLLite database, I think it is hard to sync two databases between two eDGes without any aid tool. And I also wish entrourage could add a function to help us export annotations so that we can find a way to convert it by ourselves.