Bookends IOS is working very well I find. One request: at some point is there a plan to less us manage groups - sort, put inside folders etc?
I personally work with articles in static groups and like them sorted alphabetically as there are quite a few. They are in apple pie order on the macs but random on the IOS devices
This bug will be fixed in the next update, but unfortunately, BOT library should be deleted (Settings -> Empty Library) and then re-downloaded from the cloud.