Cobalt turns your Kobo into an open e-ink app platform

You can now run custom Rust apps on your Kobo e-reader without replacing the stock operating system.

BandarLabs released Cobalt, an open-source platform that brings a launcher, app store, and Rust SDK to Kobo hardware. After a single initial setup over USB, you can install, update, and remove apps directly over Wi-Fi. The platform already includes an arXiv paper reader, a panel terminal, a Hacker News client, and a coding agent approval tool.

Why it matters: It turns locked-down e-ink hardware into a safe development target. Every app runs as a sandboxed, unprivileged process with capability-gated access to network and storage. A simple device reboot brings you right back to the standard Kobo reader interface.

Know this: Setup currently requires a Kobo Clara BW (model N365). Building a custom tool takes one Rust file using Cobalt's SDK, and merging an app PR automatically builds, signs, and publishes the binary to the catalog without needing a full system release.

Your e-reader just doubled as a distraction-free hacking platform.