So what's stopping new eReaders being released at a cheap(er) price? As I understand it, Google requires Android devices to have colour screens and, so I've read, won't certify eInk eReaders for newer versions of Android. Unless you're prepared to get technical, you can only read Amazon books on your Amazon Kindle paid for with your Amazon wallet. Some people have tried building open source eReaders but they're either abandoned, not suitable for production, or ridiculously expensive. Other than Kobo and Amazon, no book retailer wants to stray outside their core competency to develop and subsidise hardware.