So there was: InkBox OS, mostly for Kobo but with some Kindle support, it became QuillOS (wirh the same focus on devices) but when Kobo went with secureboot the

So there was: InkBox OS, mostly for Kobo but with some Kindle support, it became QuillOS (wirh the same focus on devices) but when Kobo went with secureboot the whole thing moved to the PineNote. But all of that is very outdated now...