I’m scared of installing koreader on my kobo. Right now my kobo syncs to my calibre web server seamlessly. Does koreader have the ability to sync your library to a calibre web instance?
On mine, koreader is an app that you launch, and the stock interface seems to unload completely until you exit koreader. Then the whole "OS" is still there untouched and you can get books from hell dimensions like Overdrive.
Despite never using the stock interface anymore I've left it alone because it's not much of a bother to relaunch koreader or Plato on the rare occasions that I have to.