I searched for each of the supported eInk devices and they were all tiny. Anyone know if there is a larger reader (maybe Paperwhite size-ish) that might run this?

The "Hardware" link indicates that the BoM specifies a "24-pin SPI e-paper for GoodDisplay panels (3.97″, 4.26″, 7.5″ and up)." A search turns up this: https://www.good-display.com/product/516.html

I've never heard of any of them; I guess it's geared toward build-it-yourself or kit-type devices? I can't imagine a serious aftermarket FW not supporting a single Kindle or Kobo device.

Ask amazon and Kobo to open their system if it's so important for you. The devs have probably more interesting things to do than playing wack-a-mole with a multi-billion organisation

I'm not knocking the devs for the choice to target open hardware, only remarking that that choice signals the project is for hackers, not regular consumers.

I mean, a) regular consumers are just gonna buy a Kindle, do nothing with its software, and only buy books from Amazon. But also b) the way a lot of these hobby things expand is that if they get some market traction, someone starts making and selling pre-assembled, retail-friendly versions of the thing. Look at wacky keyboards, for instance: Used to be that you had to solder your own weird ergo split, now there are companies like ZSA and Keebio that'll make really nice versions as finished products.

I would say that there is no such thing as firmware targeted for regular consumers. Regular consumers do not know what firmware is.

I am still disappointed that there is no kindle sized hardware that this can run on, but I think that has to do with manufacturers rather than firmware developers.

ESP32-S3 is really too underpowered for larger e-ink devices.