Name: Cobalt
Rating: 4.0 (1 reviews)

Cobalt is an open-source app platform for Kobo e-readers: a launcher, a signed App Store, a Rust SDK, and a capability-isolated runtime. One USB install; every app after that arrives over Wi-Fi.

Bought a used Kobo specifically to try this after seeing the HN thread. The Claude Code / terminal controller app is the killer feature for me - I do long agent sessions and my eyes were done with staring at a laptop screen for the "watch it think" parts. Sideloading over Wi-Fi after the one-time USB setup is exactly the right tradeoff, most e-ink hacking projects make you plug in a cable every single time which kills the habit fast.

Device support list is still short - my older Kobo model isn't on it yet, so I had to buy a newer used one specifically to try this. Also the app store is pretty thin right now, which makes sense for a launch, but it needs more third-party apps beyond what the team built themselves to really justify calling it an app store.

Looked at just running a normal Android tablet in grayscale mode instead, but that's a battery-life and eye-strain compromise, not a real e-ink experience. Nothing else gets you an actual app store on real e-ink hardware without a jailbreak-and-pray process.

Cobalt

Your Kobo can run apps now

Your Kobo can run apps now

Cobalt Reviews

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