---
title: "iOS App Localization & App Store Translation — Develak"
description: "iOS app localization by Develak: String Catalogs, translated interfaces, localized App Store listings and screenshots in your users’ own language."
url: https://develak.com/services/app-localization/
language: en
updated: 2026-09-27
source: Develak
translations:
  fr: https://develak.com/fr/services/localisation-application.md
---

Canonical page: <https://develak.com/services/app-localization/>

# iOS app localization: speak your users’ language

Develak localizes iOS apps end to end: String Catalogs, translated interfaces, localized App Store listings and screenshots, and testing in every language. Our own apps ship in up to 44 languages, and we built Xlocalize, a Mac app that translates .xcstrings files.

[Start a project](https://develak.com/contact/) [Explore our apps](https://develak.com/apps/)

- String Catalogs
- .xcstrings
- Plurals
- Right-to-left
- Localized ASO

## What is iOS app localization?

Localization adapts an app to another language and region. It covers every string of the interface, but also plurals, dates, numbers, currencies and units, layouts that must stretch for longer words, and right-to-left scripts such as Arabic and Hebrew. Done well, users forget the app was ever written in another language.

The modern way to localize an iOS app is the String Catalog: a single .xcstrings file, introduced with Xcode 15, that holds every string, its translations and its plural variants. We set it up properly — extraction, comments for translators, variants — so each new release stays in sync across languages.

Localization also multiplies your reach on the App Store, where each locale has its own metadata and its own search results — see our [App Store Optimization](https://develak.com/services/app-store-optimization/) service. Our full method is explained in the guide [How to localize an iOS app with String Catalogs](https://develak.com/blog/localize-ios-app-xcstrings/).

### At a glance

- **Service**: Localization of iOS apps and App Store listings
- **Format**: String Catalogs (.xcstrings)
- **Scope**: Interface, metadata, screenshots, testing
- **Our practice**: Our own apps ship in up to 44 languages
- **Tooling**: Xcode and Xlocalize, our own Mac app
- **Works best with**: App Store Optimization

Guides to go further

- [How to localize an iOS app with String Catalogs](https://develak.com/blog/localize-ios-app-xcstrings/): Guide
- [App Store submission checklist](https://develak.com/blog/app-store-submission-checklist/): Guide

## What our localization service includes

Everything that has to change when your app changes language.

- **String Catalog setup**: We migrate or configure .xcstrings, extract every string and add context comments so translations are accurate.
- **Translation & adaptation**: Interface text translated and adapted for each market, with terminology kept consistent across the app.
- **Plurals, dates & formats**: Plural rules and number, date, currency and unit formats handled by the system, never by hand.
- **Layout & right‑to‑left checks**: Screens tested for long words, large Dynamic Type sizes and right-to-left languages.
- **Localized App Store listing**: App name, subtitle, keywords, description and screenshot captions for each locale.
- **Linguistic QA on device**: Every language reviewed in the running app, on a real device, before release.

## One file, every language

All the text of your app lives in a String Catalog: every key, every language and every plural form, kept in sync by Xcode at each build.

- **Plurals done right**: English has two plural forms, Arabic six and Japanese one. The catalog stores each variant, so counts always read naturally.
- **Right‑to‑left included**: Arabic and Hebrew mirror the whole interface. SwiftUI handles most of it; we check the rest on device.
- **Nothing left behind**: Xcode flags new and changed strings, so a translation cannot silently go missing from an update.

## Who should localize their app?

If people outside your home market could use your app, localization is often the most effective update you can ship.

- **Apps with international potential**: Utilities, health, sports and hobby apps travel well: the need is universal, only the language changes.
- **Apps plateauing in one market**: New countries mean new search results and new users, without changing the product itself.
- **Developers drowning in strings**: Your app grew and the strings got messy. We move you to String Catalogs and a clean workflow.

## What you receive

A localized app, localized listings, and a workflow that keeps them in sync.

[Start a project](https://develak.com/contact/)

- A clean String Catalog (.xcstrings) for the whole app
- The interface translated into every target language
- Localized App Store metadata for each locale
- Localized screenshot captions
- Checked layouts, plurals and formats
- Right-to-left review where relevant
- A glossary of your product terms
- A workflow to translate future updates

## How we localize your app

Groundwork once, then every language follows the same path.

1. **Audit**: We check how strings are defined, find hard-coded text and flag layouts that won’t survive longer languages.
   You get: Localization audit
2. **Prepare**: String Catalog set up, strings extracted, context comments written and plural variants defined.
   You get: String Catalog
3. **Translate**: Interface and store metadata translated, then adapted to each market’s conventions and search terms.
   You get: Translated UI & listing
4. **Test**: Every language checked in the running app: truncation, plurals, formats and right-to-left layouts.
   You get: QA in every language
5. **Release & maintain**: Localized build and listings shipped together, with a process that keeps new strings translated.
   You get: Localized release

## How long does app localization take?

The first languages take the longest, because the groundwork happens once. As a guide:

1. **Audit & String Catalog**: Typical duration: A few days
   Strings extracted and commented.
2. **Translation**: Typical duration: Days to a few weeks
   Interface and store metadata.
3. **QA on device**: Typical duration: A few days
   Every language, every screen.
4. **Release**: Typical duration: With your next update
   App and listings together.

Guidance, not a guarantee: the number of languages and strings sets the real schedule.

## The localization toolkit

Apple’s native localization stack, plus a tool we built because we needed it ourselves.

[The full toolbox](https://develak.com/about/#tech)

- **String Catalogs**: One .xcstrings file for every language.
- **Xcode**: Extraction, previews and pseudo-languages.
- **Xlocalize**: Our Mac app that translates .xcstrings files.
- **Foundation formatters**: Dates, numbers and currencies per locale.
- **Plural variants**: The grammatical rules of each language.
- **SwiftUI previews**: Every screen checked in every language.
- **App Store Connect**: Localized metadata and screenshots.
- **Right-to-left layouts**: Mirrored interfaces for Arabic and Hebrew.

## Localization is how we ship every app

Every Develak app is localized, most of them into dozens of languages — and we built our own translation tool for String Catalogs along the way.

[See all 34 apps](https://develak.com/apps/)

- **[Xlocalize](https://develak.com/apps/xlocalize/)**: Localize xcstrings
  Our Mac app that translates String Catalogs
  Developer Tools · Mac
- **[Corkwell](https://develak.com/apps/corkwell/)**: Wine Cellar Manager
  Available in 44 languages
  Lifestyle & Hobbies · iPhone
- **[Seizly](https://develak.com/apps/seizly/)**: Seizure Diary
  Available in 44 languages
  Health · iPhone
- **[Pillio](https://develak.com/apps/pillio/)**: Pill Reminder & Tracker
  Available in 33 languages
  Health · iPhone · Rated 4.5 out of 5 from 89 ratings

## App localization: your questions

What developers and publishers ask us about localizing an iOS app.

**Ask your question** Not covered here? Write to us — we answer every message ourselves.

[contact@develak.com](mailto:contact@develak.com)

### What is the difference between translation and localization?

Translation converts text into another language. Localization adapts the whole experience: plurals, dates, currencies and units, layouts for longer words, right-to-left scripts, and the App Store listing and screenshots of each market.

### What are String Catalogs (.xcstrings)?

String Catalogs are Apple’s localization format, introduced with Xcode 15. A single .xcstrings file stores every string of an app, its translations, its plural variants and comments for translators, replacing the older .strings and .stringsdict files.

### How many languages should my app support?

Start with the markets where your category is popular and competitors are weak — usually a handful of major languages — then expand based on data. Develak’s own apps ship in up to 44 languages, but more is not always better for a first step.

### Do you use machine translation?

Our workflow combines AI-assisted translation with human review. Xlocalize, our Mac app, translates String Catalogs with models such as Claude, GPT or Gemini, using translator comments as context; every language is then reviewed in the running app. For sensitive wording such as medical or legal text, we recommend a review by a native speaker and can work with your own translators.

### Do you also localize the App Store listing?

Yes. Name, subtitle, keywords, description, promotional text and screenshot captions are localized for each locale. It is often the part with the highest return, because it opens up search results in every country.

### Can you localize an app we built ourselves?

Yes. We audit your project, move it to String Catalogs if needed, then handle translation and testing. Your team keeps a clean workflow for future releases.

### Do you support right-to-left languages like Arabic?

Yes. SwiftUI mirrors layouts automatically for right-to-left languages such as Arabic and Hebrew; we then check every screen for icons, alignment and custom views that need attention.

## Related services

[All services](https://develak.com/services/)

### [App Store Optimization](https://develak.com/services/app-store-optimization/)

Keyword research, titles, screenshots and localized metadata that help people find — and download — your app.

### [iOS app development](https://develak.com/services/ios-app-development/)

Native iPhone and iPad apps in Swift and SwiftUI, built end to end and released on the App Store.

### [App maintenance](https://develak.com/services/app-maintenance/)

Updates for each new iOS, bug fixes, crash monitoring and new features — so your app stays fast, compliant and well rated.

## Take your app worldwide

Tell us which markets you have in mind. We’ll suggest where to start.

[Start a project](https://develak.com/contact/) [contact@develak.com](mailto:contact@develak.com)

---

*Markdown version of <https://develak.com/services/app-localization/> for AI assistants, published by Develak. Links lead to the web pages; add .md to a page URL for its Markdown version. Site index: <https://develak.com/llms.txt>.*