Kindle

FreeInk ships an open-source stack for e-paper readers: software, firmware, and a build-it-yourself PCB, aimed squarely at ESP32-class chips like the ones inside cheap Chinese readers such as the Xteink X4.

Half the Hacker News thread showed up asking for a Kindle, Kobo, or reMarkable port anyway. A self-described veteran electronics engineer had the same answer for every request: wrong chip entirely, nothing a firmware update could fix.

The on-screen message draws the line: previously downloaded books still open, but the device can no longer pull new purchases from the Kindle store. So he built a workaround, buy on Amazon, torrent a DRM-free copy, sideload over USB, and admits the purchase step now delivers no benefit whatsoever.

Not everyone sees malice. One reader whose own older Kindle still sideloads says the block only hits the store on end-of-life devices, whose ancient built-in browser was never going to last.

The Xteink X4 arrives with a 16GB microSD card, a MagSafe ring, and stock firmware locked to three fonts and a Chinese default menu. The reviewer flashed it anyway and got TeX-quality justification out of a microcontroller.

Then the thread turned into a confessional: owners who can't stop buying more, a custom-firmware author testing a build, and one screen that shattered in a backpack.