# Device, theme and cassette

CHLOE//OS is the `dev.chloe.os` native companion plus Lawnchair and artwork on Android 13. It is not a custom Android ROM. The main home screen, lock screen and music subscriptions are separate surfaces.

| Surface | Editable source |
|---|---|
| Change me / Workbench / Creations guide | `companion/src/dev/chloe/os/MainActivity.java` |
| Portrait cassette and playback controls | `companion/src/dev/chloe/os/CassetteActivity.java` |
| Home playback widget | `companion/src/dev/chloe/os/MusicWidget.java` and `MediaBridge.java` |
| Native shared color fields | `MainActivity.java`; cassette/widget have their own colors |
| Home wallpapers | `companion/assets/violet.png`, `pink.png`, `midnight.png` |
| Lock wallpaper | `companion/assets/lock.png` |
| Character artwork | `companion/assets/portrait.png`, `developer-chloe.png` |
| Home icons and folders | Lawnchair long-press UI; launcher backup before editing |
| Editable color reference | `theme/palette.json` |

`node developer/skill/chloe-os/scripts/chloe.mjs palette` validates the palette JSON. `palette --apply` updates the six named MainActivity color fields and saves a source backup. It does not recolor raster wallpapers, cassette art or the widget; edit those separately when asked. This distinction matters: changing a JSON file alone does not change the whole device.

Build: `chloe.mjs build companion`. Install: `chloe.mjs install companion CHLOE-OS-Companion.apk`. The existing companion key must be present. Keep package `dev.chloe.os`, the widget provider and notification listener names. Increment Android versionCode for a new release, preserving activity aliases referenced by her home shortcuts. Applying a wallpaper can be done through the on-device Themes screen after the update.

Verify the requested screen and existing cassette/provider controls when touched by the change. Capture a real screenshot. Use Android's document picker for local sources; the public site is only the laptop entry point. A stock FiiO logo during firmware startup cannot be replaced by changing the companion; prefer the existing editable startup animation study, not bootloader work.