feat(android): add mobile browser app setup

.gitignore

@@ -26,3 +26,10 @@ third_party/sparkle/
 
 website/.next/
 website/out/
+
+android/.gradle/
+android/.idea/
+android/local.properties
+android/**/build/
+android/captures/
+android/.kotlin/

AGENTS.md

@@ -12,13 +12,17 @@ This file gives Codex project-specific context for working in Dao Browser.
 
 Dao Browser is a Chromium-based browser with an Arc-style vertical sidebar, currently targeting macOS arm64. The full Chromium checkout and build output live under `engine/`, which is gitignored and very large. This repository tracks Dao-owned code and patch files, not the whole Chromium tree.
 
-Read `docs/features.md` first when asked what Dao Browser does, when locating the owner of a behavior, or before adding a feature that may overlap with existing work.
+Read `docs/features.md` first for desktop Chromium behavior and
+`docs/features-android.md` first for Android GeckoView behavior when asked what
+Dao Browser does, when locating the owner of a behavior, or before adding a
+feature that may overlap with existing work.
 
 ## Feature Documentation
 
-- When adding or materially changing a Dao Browser feature, update `docs/features.md` in the same change to keep the feature catalog current.
-- When adding or materially changing a Dao Browser feature, update `docs/feature-checklist.md` in the same change so Chromium upgrade and regression checks cover the new behavior.
-- If a feature change does not require updates to either document, explicitly mention why in the final response.
+- When adding or materially changing a desktop Chromium feature, update `docs/features.md` in the same change.
+- When adding or materially changing an Android feature, update `docs/features-android.md` in the same change.
+- When adding or materially changing a feature on either platform, update `docs/feature-checklist.md` so upgrade and regression checks cover the behavior.
+- If a feature change does not require updates to its platform feature inventory or the shared checklist, explicitly mention why in the final response.
 
 ## Source Of Truth
 
@@ -128,8 +132,9 @@ Never hardcode user-facing copy in Dao-owned UI. All user-visible text must have
 - C++ Views strings go in `src/dao/browser/strings/dao_strings.grd` and are read with `l10n_util::GetStringUTF16` or `GetStringFUTF16`.
 - Sidebar WebUI strings go in `src/dao/browser/strings/dao_strings.grd`, are registered on the sidebar `WebUIDataSource` with `AddLocalizedString` / `UseStringsJs`, and are read from TypeScript through `loadTimeData.getString(...)`.
 - Agent WebUI strings go in `src/dao/browser/ui/webui/resources/agent/i18n/locales/en.ts` and are read with `t('key', { var: 'x' })`.
+- Android strings use `android/app/src/main/res/values/strings.xml` as the English source and qualified `values-*/strings.xml` files for translations. Android follows the system locale and falls back to English.
 - `zh-CN` is hand-authored and treated as the tone reference.
-- Other locales are generated manually by the user via `OPENAI_API_KEY=... sh ./i18n.sh`; do not run it automatically.
+- Other desktop and Android locales are generated manually by the user via `OPENAI_API_KEY=... sh ./i18n.sh`; do not run it automatically. The root command dispatches independent platform translators, and `--only desktop` or `--only android` limits the run.
 
 ## Native Toast Feedback
 

android/NOTICE.md

@@ -0,0 +1,40 @@
+# Third-party Notices
+
+Dao Browser Android consumes Mozilla Android Components and GeckoView under the Mozilla Public License 2.0.
+
+- Mozilla Public License 2.0: https://www.mozilla.org/MPL/2.0/
+- Android Components source: https://searchfox.org/firefox-main/source/mobile/android/android-components
+- GeckoView source: https://searchfox.org/firefox-main/source/mobile/android/geckoview
+
+The release packaging task must generate the complete transitive dependency notice set before public distribution.
+
+## uBlock Origin
+
+Dao Browser Android bundles a GeckoView compatibility variant of the Firefox
+extension from uBlock Origin 1.72.2 under the GNU General Public License 3.0.
+The variant removes only the GeckoView-unsupported `menus` permission and
+`commands` manifest entry; blocking code and filter assets are unchanged.
+
+- Source: https://github.com/gorhill/uBlock
+- Release: https://github.com/gorhill/uBlock/releases/tag/1.72.2
+- Artifact: `uBlock0_1.72.2.firefox.signed.xpi`
+- SHA-256: `40c315b0da7871868155ecfae7a50a58dfa0920aebd865e008214986f1b7c578`
+- License text: `third_party/ublock_origin/LICENSE.txt`
+
+The corresponding source is available from the source and release links above.
+Release packaging must preserve this notice, license text, and source access.
+
+## KISS Translator
+
+Dao Browser Android bundles the unmodified public Firefox extension KISS
+Translator 2.0.29 under the GNU General Public License v3.0 only.
+
+- Source: https://github.com/fishjar/kiss-translator
+- Release: https://github.com/fishjar/kiss-translator/releases/tag/v2.0.29
+- Listing: https://addons.mozilla.org/firefox/addon/kiss-translator/
+- Artifact: `kiss_translator-2.0.29.xpi`
+- SHA-256: `0316f026b1b0c3d171262b3f4f369e34013abdf1d1bbe9d348290c3db53f4092`
+- License text: `app/src/main/assets/notices/kiss_translator_license.txt`
+
+Translation is performed through the service selected inside KISS Translator.
+Release packaging must preserve this notice, license text, and source access.

android/README.md

@@ -0,0 +1,110 @@
+# Dao Browser Android
+
+Dao Browser Android is a Kotlin application built with Mozilla Android Components and GeckoView.
+
+## Requirements
+
+- macOS on the existing development Mac
+- JDK 17
+- Android SDK 36
+- An Android API 26+ emulator or physical device
+
+Set the local SDK location before running Gradle, for example:
+
+```bash
+export ANDROID_HOME="$HOME/Library/Android/sdk"
+```
+
+All commands run locally on the development Mac; they do not require a cloud build service or paid device hardware.
+
+## Verify
+
+```bash
+cd android
+./gradlew :app:verifyBundledUBlockOrigin
+./gradlew :app:verifyBundledKissTranslator
+./gradlew :app:testDebugUnitTest :app:lintDebug :app:assembleDebug
+```
+
+The APK bundles a GeckoView-compatible uBlock Origin 1.72.2 package and the
+unmodified KISS Translator 2.0.29 Firefox package. Both are
+requested as built-in extensions before creating the first browser session and
+update with the APK without a first-run download. KISS Translator supplies
+paragraph-by-paragraph bilingual page translation, input and selected-text
+translation, and subtitle translation through the service selected inside the
+extension.
+
+The Extensions screen reads installed extensions from Gecko and can toggle
+them. Its Store is native Compose UI: a blank query loads AMO recommendations,
+submitted queries search AMO, and catalog requests are limited to Android
+extensions compatible with the running Gecko major version. The catalog accepts
+only public HTTPS `.xpi` packages and installs the selected AMO package directly
+through Gecko's `RTAMO` path. Opening, searching, or installing from the Store
+does not change the selected browser tab.
+
+Before either Store or local installation completes, Dao presents Gecko's
+requested browser permissions, site access, and data-collection permissions for
+explicit approval; cancellation declines the install. The system document picker
+remains available for local `.xpi` files without a storage permission. That
+package is staged for Gecko's `FROM_FILE` path until the installation reaches a
+terminal result. User-installed extensions persist across restarts and can be
+disabled or uninstalled. Release GeckoView enforces Mozilla signatures,
+compatibility, and blocklists for both install paths, so Dao does not bypass
+unsigned, incompatible, corrupt, or blocklisted-package rejection. Catalog
+failures show a Retry action. Remote installation failures use the localized
+extension-install status; after the user dismisses the result with Done, the
+add-on's Install action is available again. A dedicated Dao ad-blocking
+preference is not implemented.
+
+## Localization
+
+Android uses English as its unqualified source catalog and follows the system
+locale through standard Android resource resolution. Simplified Chinese is
+hand-authored under `values-zh-rCN`; unsupported locales fall back to English.
+Desktop and Android localization files remain independent.
+
+From the repository root, preview translation work without making API calls or
+writing files:
+
+```bash
+sh ./i18n.sh --dry-run
+sh ./i18n.sh --only android --langs zh-CN,ja --dry-run
+```
+
+Run the desktop and Android translators with OpenAI GPT-5.5:
+
+```bash
+OPENAI_API_KEY=sk-... sh ./i18n.sh
+```
+
+Use `--only desktop` or `--only android` to run one platform, and use
+`OPENAI_TRANSLATE_MODEL` or `--model` to override the default model. A live run
+uses the OpenAI API and may incur charges; build and test commands never invoke
+it automatically.
+
+## Install
+
+```bash
+cd android
+./gradlew :app:installDebug
+```
+
+## Device smoke test
+
+```bash
+cd android
+./gradlew :app:connectedDebugAndroidTest
+```
+
+The application uses Mozilla Android Components `BrowserStore` and
+`EngineMiddleware` for multiple Gecko tabs. Its full-screen tab grid supports
+live tab counts, switching, close and swipe-right-to-close, new tabs, and real
+page thumbnails. Android Components `SessionStorage` restores regular tab order,
+selection, URLs, and navigation history after process death; private tabs and
+their thumbnails are never persisted.
+
+It also supports address-or-search navigation, persistent
+history/bookmarks/folders, Android system downloads, persistent engine
+preferences, default-private startup, signed extension installation and
+management, and CameraX QR scanning. An in-session private-mode switch,
+passwords, sync, Agent, and MCP are not yet implemented.