Pretty much all of them are actually running linux, but are also proprietary. You could try the Pine Note, but Kobo and Pocketbook are reasonably open as far as

Pretty much all of them are actually running linux, but are also proprietary. You could try the Pine Note, but Kobo and Pocketbook are reasonably open as far as these things go. These devices are mostly disposable though due to the designed-in fragility, so I wouldn't bother obsessing over the software - you'll need a new one in a year or two.