Cobalt 0.3.18 beta

Immutable prerelease built from the beta branch at 08f4bd8.

Cobalt 0.3.17 beta

Immutable prerelease built from the beta branch at 5cf94cf.

Cobalt 0.3.16 beta

Immutable prerelease built from the beta branch at 13761c0.

Cobalt 0.3.15

Cobalt 0.3.15

Keeps older apps running after a platform update, adds fully tested Libra H2O support, fixes radio handling on more Kobo hardware, and expands the host companion tools.

Fixed

• Apps that greet with protocol 11, 12, or 13 now receive every runtime frame on that same protocol. This fixes Todo, Gutenbird, and other older binaries immediately exiting with UnsupportedVersion(14) after a platform update (#192; reported by @seasonalcarchofa in #191).
• Wi-Fi is detected from the interface the kernel marks as wireless instead of assuming wlan0, including older Realtek devices that call it eth0 (#186, @teonbrooks).
• A Bluetooth backend is offered only when a controller is present, and Settings no longer shows toggles for missing radios (#187, #188, @teonbrooks).
• Cobalt reaps the stock Wi-Fi supplicant when leaving on Libra Colour firmware 4.46, preventing a shutdown crash (#190, @RG007JM).
• Updated rustls to 0.23.45 for RUSTSEC-2026-0285 (#193).

Devices

• Added fully tested support for Kobo Libra H2O N873 (device code 384) on firmware 4.38.23697, with attended display, touch, exit, and recovery evidence (#185, @teonbrooks).

Host tools

• The kobo command now has a numbered owner menu and searchable setup guides for the full Store catalog.
• Paperterm gains connection checks and named presets; Flashcards gains import review and local previews; Frame gains crop/pad previews and recovery; Sidekick gains guided setup (#181, #182).

Full changes: v0.3.13...v0.3.15

Cobalt 0.3.15 beta

Cobalt 0.3.15 beta

Keeps older apps running after a platform update, adds fully tested Libra H2O support, fixes radio handling on more Kobo hardware, and expands the host companion tools.

Fixed

• Apps that greet with protocol 11, 12, or 13 now receive every runtime frame on that same protocol. This fixes Todo, Gutenbird, and other older binaries immediately exiting with UnsupportedVersion(14) after a platform update (#192; reported by @seasonalcarchofa in #191).
• Wi-Fi is detected from the interface the kernel marks as wireless instead of assuming wlan0, including older Realtek devices that call it eth0 (#186, @teonbrooks).
• A Bluetooth backend is offered only when a controller is present, and Settings no longer shows toggles for missing radios (#187, #188, @teonbrooks).
• Cobalt reaps the stock Wi-Fi supplicant when leaving on Libra Colour firmware 4.46, preventing a shutdown crash (#190, @RG007JM).
• Updated rustls to 0.23.45 for RUSTSEC-2026-0285 (#193).

Devices

• Added fully tested support for Kobo Libra H2O N873 (device code 384) on firmware 4.38.23697, with attended display, touch, exit, and recovery evidence (#185, @teonbrooks).

Host tools

• The kobo command now has a numbered owner menu and searchable setup guides for the full Store catalog.
• Paperterm gains connection checks and named presets; Flashcards gains import review and local previews; Frame gains crop/pad previews and recovery; Sidekick gains guided setup (#181, #182).

Beta Store

The existing signed beta catalog already contains the app updates from #181 and #182: Crossword, Deck, Flashcards, Frame, Gallery, Gutenbird, Lichess, LogicPack, Paperterm, Read Later, Sidekick, and Verses. This platform cut changes no Store inputs, so app-catalog-beta was verified and intentionally not republished.

What to test

• Update an existing Beta-channel device without clearing installed apps or state.
• Launch an existing protocol-13 Todo or Gutenbird build, then launch protocol-14 Settings.
• On Libra Colour firmware 4.46, leave Cobalt while Wi-Fi is enabled and confirm the stock reader resumes normally.
• On Libra H2O, confirm Wi-Fi is available through eth0 and Settings does not offer Bluetooth controls.
• Confirm return to the stock reader and rollback while preserving apps, state, and secrets.

Build

• Platform source: 4bb0d0e2c66e8d729dc10a66e606cd58da42b936
• Device archive SHA-256: 4c6550faf30726d8c0dfcdfff2206923261c7dfcc0d566f668417bfc2a46f0b1
• Beta Store source: 1955167edf56604afe1d28f533ab35860c60f8ba
• Beta Store catalog SHA-256: 17e28b3498efda065b51c26fc50c09fa2e1fbc12dbb85c87ff10a85b604649fe

Full changes: beta-v0.3.14...beta-v0.3.15

Cobalt 0.3.14 beta

Immutable prerelease built from the beta branch at a409e7e.

Cobalt 0.3.13

Cobalt now runs on Kobos and firmware apart from officially tested ones, after giving a warning and user consent. A firmware update from Kobo no longer takes the
platform off a reader until somebody re-tests that exact build.

Upgrading from 0.3.9

Updates over Wi-Fi as usual. Applications, data, secrets and trust roots are
preserved. 0.3.10 to 0.3.12 were beta-only; this release carries all of them.

Added

• Devices and firmware outside the tested matrix start, after showing what has not been tested and asking to continue once. Accepting is remembered per model and firmware series; declining asks again next time (#175)
• A full-screen logo covers the startup wait instead of a blank screen (#175)
• Papers show their mathematics and tables as mathematics and tables rather than flattening them to text (#172)
• Every application page offers the browser install (#152)

Changed

• A tested firmware now covers its whole release series, so the build numbers Kobo ships within a series are taken without asking. The device code, model prefix and kernel release are still matched exactly (#175)
• Firmware that NickelMenu cannot hook is refused rather than installed onto, since nothing could start what was installed (#175)
• The Store asks for the newest releases rather than all of them (#153)
• Shared application foundations, and simulator checks that repeat (#167, #155)

Fixed

• The Elipsa 2E starts when held in either portrait orientation (#151)
• Skip buttons stay inside their slots when more than one habit is due on a weekday (#150)
• Catalog publication checks no longer trip on simulator-only changes (#166)

Verify the download against the .sha256 file, or let the installer do it.

Cobalt 0.3.13 beta

Immutable prerelease built from the beta branch at 3b2211a.

Cobalt 0.3.12 beta

Immutable prerelease built from the beta branch at c22c946.

Cobalt 0.3.11 beta

Immutable prerelease built from the beta branch at 996a10b.