[sasvari]

> 1. I already have an ebook library in Calibre that I access on other devices, the sync feature allows me to seamlessly integrate into my other devices.

just out of curiosity: I sync my Kindle with Calibre in a very seamless way, too. what is the main difference here?

[eduardo_roboto]

If you are referring to syncing over USB or sending via email, that's the difference. Calibre can be run as a service, allowing KOReader to access it wirelessly. You can copy books and sync the progress back to Calibre for sharing between devices.

[Rinzler89]

Same, I also find that point of his perplexing as I could always sync my Tolino (German Kobo clone) to Calibre out of the box without any third party tools or hacks.