Localization is more than replacing English words. A multilingual application needs decisions about writing direction, number and date formats, plural forms, fonts, and what happens when one translation is missing. These decisions are especially visible when a product serves Arabic, Kurdish, and English readers.

Keep messages outside widgets

Flutter's localization tooling supports generated message accessors and ARB resources. Give messages stable identifiers and helpful translator descriptions. Use placeholders for values and plural messages for counts instead of assembling sentences from fragments whose word order may be wrong in another language.

For example, a saved-items message should let the translation express zero, one, and other relevant counts as a complete message. Do not assume that adding an English “s” or switching between two strings captures every language's grammar.

Choose the language and script precisely

Kurdish is not a single layout assumption. Confirm the intended language variety, script, and locale identifiers with the product owner and translators. Check whether the Flutter SDK and packages you use include the required framework translations. Application messages alone do not localize every built-in date picker or dialog.

Prefer directional layout rules

Use start/end alignment and directional padding where the interface should follow reading direction. Review arrows individually: navigation arrows may mirror, while a media-play symbol or a brand mark may not. Mixed content such as phone numbers, email addresses, and order identifiers needs hands-on testing inside right-to-left paragraphs.

Design fallbacks before launch

Decide the default locale and how the app responds to unsupported device languages. Keep a user's explicit language preference separate from device settings. Avoid a screen that combines three languages because each component chose its own fallback independently.

Use a multilingual acceptance pass

  • Test long labels in a narrow window.
  • Review singular, plural, and zero-item messages.
  • Verify text input, selection, and validation errors.
  • Check dates and numbers with realistic user data.
  • Test deep links and restored screens after changing language.
  • Have a fluent reviewer check meaning and tone.

Keep the technical work and language review connected. A technically correct locale file can still produce confusing instructions, and a good translation can still be clipped by an inflexible layout.

Official reference: Internationalizing Flutter apps.