[VelvetElvis]

So this appears to be just another Android ereader app, not a replacement for Calibre Companion/Calibre Sync. Or am I missing something?

Not to sound rude, but there are probably dozens of ereader apps, but no viable Android replacements for the aforementioned Calibre library apps. Or can your app act as such?

EDIT: Hmm.. Not available for my jailbroken 10th gen. Fire HD8, which did work well with CC and CS.

BTW.. The FAQ works in Chrome, but not in Firefox or Edge. Page renders, but dropdowns don't work.