[themadturk]

I've tried hard to make Bookshelf work for me, but I find the UI confusing, going off in unexpected directions, and it's very unintuitive. I've got SimpleUI at the moment and it's comfortable, even though the library interface is lacking.

[jerojero]

Grimmory is pretty good as a calibre alternative. I use that and connect through the OPDS to koreader. Works well.