Cobalt brings a signed app store and Rust-based app platform to Kobo e-readers without replacing the stock reader

Cobalt is an open-source platform that lets Kobo e-readers run third-party apps through a launcher, signed App Store, Rust SDK, and sandboxed runtime. Users install it once over USB, then manage apps over Wi-Fi, while a reboot returns the device to the standard Kobo reading experience.

The project turns dedicated e-readers into low-power, purpose-built computing devices without requiring a full jailbreak-style replacement of the core experience. Its use of signed apps and isolated processes suggests a more secure path for community software on consumer hardware, potentially broadening what e-ink devices can do beyond books.