Internationalization

The app UI is bilingual: Spanish and English. Everything else in the repository (code, docs, commits) is English only.

Rule

No user-facing string is ever hardcoded. Every string lives in strings.xml and is referenced via stringResource(...). Adding a string means adding it to both locales in the same change.

Resource layout

res/
├── values/        strings.xml   ← default, English
└── values-es/     strings.xml   ← Spanish

• Default (values/) is English. Spanish is values-es/.
• The device locale selects the language automatically; a future in-app language override can force one via AppCompatDelegate.setApplicationLocales / per-app language settings.

Conventions

• Key naming: screen_element_purpose, e.g. reader_action_next_page, library_continue_reading_title.
• Use plurals (<plurals>) for counts, never string concatenation.
• Use placeholders (%1$s, %1$d) with positional args so word order can differ between languages.
• Format dates/numbers with locale-aware APIs, never manual formatting.
• Content descriptions for accessibility are localized strings too.

Checklist when adding UI text

1. Add the key to values/strings.xml (English).
2. Add the same key to values-es/strings.xml (Spanish).
3. Reference it with stringResource(R.string.key) — no literals in composables.