When it comes to an eBook reader, the choices are limited. The market is dominated by Amazon’s proprietary Kindle along with a few other options like Kobo, Nook and Onyx.
An interesting news for open source enthusiasts is that a developer, Joey Castillo, is working on creating an open
There are A4 e-readers. Bamboo note for example.
Yes I’ve seen one. Maybe there are more now than when I looked, but at that time there weren’t enough to be able to make a choice as a consumer.
Onyx Boox has the Note Air 3(10in) and the Tab X(13in). They aren’t cheap though, $400 and $900 respectively, mostly because of how expensive those large eInk screens are.