

Not that I recall other than if you wanted to use their book sync function. My one gripe has been that it has to use dropbox or their cloud service to auto sync books.
Since I have an email server in house I’d rather hoped to just make an email account for it and send things via calibre that way. But manual copy or downloading via the (rather slow and basic) built in browser works too.
It’s a trap all right, but the spring is apparently busted and nobody knows how to trigger it