I built an SDK to help me create apps I wanted on my Kobo. My Kobo device has a single core <1GHz processor and 512MB RAM, much less than a Raspberry Pi, but the eInk display and larger battery life opens up a lot of use cases.
I have since used it to build an approval sidekick for my Mac's Claude code and codex, a Hacker News Client for Kobo, a Gutenberg reader, an RSS search and reader and more. All the code is in the repo.
If you have a different device than mine (Clara BW) would love for you to test it on your device and submit a PR to enable this for more device profiles.
Thanks.