I bought a book yesterday.
Today, almost 36 hours later, it still hasn't shown up on my Android. Granted, I haven't used it much today, did a daily reading and checked some things. My reading plans from my desktop have updated. Why hasn't my library?
(No, I'm not sending logs. This is an ongoing problem you know about. I've experienced it on three different devices using different versions of Android for a period of 2.5 years.)
Simplest fix would be to give us a "sync now" button on our menu. That can't be that hard, can it?