iOS Localization: How to Increase Your App's User Base

Looking to broaden your iOS app’s user base? Check out our in-depth guide on iOS localization to find out how you increase users and revenue through localization.


The App Store is available in over 175 regions globally, offering content in over 40 languages. Moreover, the marketplace experienced more than 8.1 billion app downloads in the last quarter of 2022.

As the App Store has a massive user base and experiences a higher retention rate compared to Android apps, localization is essential to success. iOS users tend to have a higher purchasing power, leading to higher revenue in the Apple App store compared to Android apps. This is why developers prefer localizing iOS apps first. In addition, iOS apps come in with built-in localization resources which makes the localization process easier. All these factors contribute to a better user experience, which could contribute to the high retention rates.

Localizing your app is a great way to reach users worldwide and ensure they have a positive experience with your product. It helps them access your app in a language and context they understand rather than relying on basic translation apps to navigate it.

But creating multiple versions of your app in different languages can feel daunting. Fortunately, we have practical tips to help you start the localization process.

In this blog post, we'll cover everything you need to know about iOS app localization — from why it's crucial to detailing the entire process.

Why is iOS app localization important?

There are several reasons why you should invest in the app localization process. Here are a few to help you decide on its potential.

Increases in-app engagement

Offer a localized in-app experience tailored to the customers’ language and culture. They will feel more at home in the app and be more likely to interact with it. Plus, having a localized iOS app removes obstacles typically associated with language learning or cultural differences. Users don’t need to use an automated translator to understand the content of your app, making it much more accessible.

Over time, more users sign up, increasing the overall engagement rate and the in-app engagement rate in that region. Localization can ultimately increase user retention, conversion, and satisfaction rates.

Improves visibility by ranking for local keywords

Localizing your iOS app is crucial when your goal is to increase the app's visibility and ranking in the App Store. Aim to rank for low-competition keywords your competitors aren't going after as part of your go-to-market strategy.

You can do this by conducting in-depth competitor and keyword research before starting the localization work. Look at keywords with a significant search volume in the App Store and include them while optimizing the app for search. This will allow customers to find your app in their language more easily.

Expands your user base faster

Localizing your iOS app accelerates the growth of your user base. You can expand your user base quickly by offering a better user experience and increasing visibility.

Plus, you can target multiple regions simultaneously or expand into neighboring regions easier when you optimize for common languages. If you localize your app in German, you can target countries like Belgium, Switzerland, and Austria without starting from scratch.

Ultimately, you access larger segments of the market faster. This way, it’s easier to identify high-performing markets and grow revenue quickly.

Increases the potential for sales

Taking the time to localize your app gives you access to more users who connect with your brand on a deeper level as they engage with the material in their own language.

Plus, when you consider the potential for earnings via the App Store, it’s a no-brainer. For instance, Apple paid over $60 billion to developers in 2022 — indicating the revenue potential of the marketplace.

Also, these apps feel inherently more user-friendly as small touches like currency conversions, payment options, and campaigns relevant to the area create higher affinity for the brand.

Gains a competitive advantage

When you think about how competitive the current market is, you should jump on any opportunity to differentiate yourself. With localization, even lesser-known companies can create digital products that are accessible and relevant for global use. It leads to increased leads, conversion opportunities, and higher revenue. You’ll also establish a better global presence over time.

Companies like Lyft have achieved this by scaling their content in eight languages. It helped them increase the blog's unique page-views by 50% for non-English users and on-page time by 29%. Ultimately, they could cater to a broader audience, gaining a competitive advantage.

How Lyft Scaled Content for 8 Languages from Smartling on Vimeo.

Difference between localization (L10n) and internationalization (I18n)

One of the most common misconceptions is that most people assume localization (L10n) is the same as internationalization (I18n). But this is far from accurate.

I18n typically precedes L10n and is more broadly concerned with creating a product that can be used across cultures and regions. The goal of i18n is to ensure all elements of the product, including its code and interface, are flexible enough to accommodate different users in different contexts.

Implementing it properly allows you to translate your app into your preferred languages without changing the source code. This process saves companies significant time, money, and resources.

On the other hand, l10 is focused on adapting a product specifically for a particular target audience in a specific region. It involves tailoring the graphics and layout of the product according to local preferences and translating content into a given region's predominant language. It also includes ensuring that technical elements like currency and date formats are accurate for each locale according to local conventions.

In short, i18n sets the foundation for l10n and ensures it happens without disruptions.

How to localize an iOS app in 5 steps

Here’s a tutorial to help you get started with the app localization process:

1. Internationalize your iOS app

Before you get started with the localization process, ensure that the app’s interface and code can be localized in the first place. For this, you need to use Apple's API, which ensures your app is internationalization-friendly.

Xcode, Apple's integrated app development environment for macOS, has a Base Internationalization feature. This feature helps you extract files from the app's code repository and create strings ready to be localized.

These files are usually in the Base.lproj folder; you can find separate folders for each location—for instance, en.lproj for English. If you need to localize a file, make sure it's present in this folder.

While this handles the interface localization, you need to ensure the hard code is ready to be localized too. For this, you need to wrap every line of hard text with the String(localized:””) code.

You can store this as a Localizable.strings file in the Base.lproj folder. Don’t forget to comment on each line to ensure your translator has the needed context.

2. Prepare your files for translation

Using Xcode, you can export all your localization files that need to be sent to the translator. Follow these steps:

  • Go to the Xcode Project Navigator
  • Click on “Product”
  • Click on “Export Localizations”
  • Type in a folder name
  • Choose a location, localizations, and screenshots
  • Click on “Export”

Note: If you’re using Smartling to manage the localization process, select only the original language (Base language/Development language) in the Xcode UI.

The app creates an Xcode Localization Catalog (.xcloc) where you can find the following:

  • Extracted strings in an XML Localization Interchange File Format (XLIFF) format
  • .stringsdict plural variants for each chosen language
  • .strings file for the localizable properties of the app
  • Source contents folder with all the necessary screenshots and content for translators

3. Integrate Smartling into your code repositories

After you export your localization files, integrate a translation management system like Smartling to manage the entire process. You can do this via our API to accomplish the following:

  • Automate uploads and downloads on your files
  • Integrate it directly with your app’s code repository
  • Visually contextualize code strings to help translators

You can upload the .strings files or .xliff files which are then sent over to the translators for content translation. Additionally, if your app uses plural strings, then upload the .stringsdict file, too.

Once complete, you can download the translated version of the .xliff file and import it back into Xcode.

4. Conduct quality assurance tests for each file

Before releasing the localized mobile app to users, ensure that the app was successfully tested in advance. You can use Smartling’s Linguistic Quality Assurance (LQA) feature to test the translation quality and rectify any mistakes before it’s imported into the app.

After you’ve validated the translations and imported the file into the app, test how it looks and performs using Xcode. Here are a few tests you can perform for this purpose:

  • Unit test: Test for the expected behavior of a particular function within the app.
  • Integration test: Test how each component interacts with others and whether they function as intended.
  • User interface test: Test whether users can complete specific tasks within the app as needed.
  • Performance test: Test your app's performance by analyzing metrics like memory used, time taken, or data written during code execution.

The main goal is to ensure the app is translated correctly, works appropriately in the new languages, and all the locale-specific settings function well. For instance, ensure that your app works with right-to-left text directionality for Arabic.

5. Publish, monitor, and iterate

Regularly monitor the performance of your iOS application to ensure that users can experience the product as intended. To gauge user satisfaction, pay attention to user feedback on various platforms, including social media, app stores, website reviews, and surveys.

Plus, you should look at analytics such as app crashes, usage flow, session length, and user engagement to determine areas needing improvement. Regularly reviewing and responding to user feedback can help build trust with users, increase customer loyalty, and provide insights on how best to update the app in the future.

You can run A/B tests to track different versions of an app against each other and identify which design elements are most successful on an individual level. In addition, conduct surveys or interviews to understand user motivations to optimize in-app experiences.

Overall, regularly monitoring the performance of an iOS app helps you stay on top of issues and offer a high-quality product at all times.

Best practices for iOS app localization

Here are a few best practices to help avoid common roadblocks when localizing your app:

1. Analyze in-app analytics and reviews to determine market demand

If you already offer your app globally, you can use App Store analytics to gain valuable insights into the potential demand for localized apps in different regions. Analyze different performance metrics such as the following:

  • Product page views
  • Sales
  • Active devices by territory
  • App units
  • Average session
  • Retention per active device

These analytics give you a better understanding of how users in that territory engage with the app. You can also review user feedback like product reviews and feature requests to identify gaps in the current version. This detailed analysis offers companies an effective way to assess the potential demand for localized apps.

2. Research region-specific nuances before localization

Conduct thorough market research into any cultural differences and nuances before localizing your iOS app. This research should involve understanding cultural values, language usage, symbols, patterns, cultural nuances, color preferences, relevant holidays, and more.

Companies like Microsoft have made similar blunders while localizing their Xbox gaming console for markets beyond the United States and the United Kingdom. Many gamers in the European, Middle Eastern, and Asian market have complained about the terrible localization experience Microsoft’s Xbox console offers.

In Belgium, it offers translations in French even though they speak Flemish/Dutch. But in countries like Japan, they only provide subtitle support.

Companies should also take great care when using art styles as part of their localization process — ensuring images are used to adhere to accepted norms within different cultures and regions.

3. Don’t forget about the visual context while translating

Handing off translations to a team in multiple files can become confusing to understand which string belongs in which app. Plus, the translator won't have the proper context for translation without an accurate understanding of what the string stands for. It can lead to inaccurate translations and costly correction cycles when they don't.

Instead, use a solution like Smartling to capture and automate visual context. This gives translators much-needed background information before starting the process. Plus, it results in higher-quality translations and faster turnaround times.

You can do this by uploading screenshots or videos using the context API and automating the process. Smartling uses Optical Character Recognition (OCR) technology to match the strings with the correct screenshots—saving everybody time in the long run.

4. Have the source content ready before starting the process

According to our Solutions Consultant, Hakim Abdus-Sabur, many customers struggle with content readiness. By content readiness, we mean having the source content ready for translation with the right visual context.

The best way to navigate this challenge is to identify a process where the copy and content get flagged for translation when it reaches a certain level of readiness. It reduces the translation time and ensures the translation workflow is ongoing and not based on individual phases.

5. Opt for tools that help you integrate automated workflows

Translation can be tedious when you consider the number of changes developers make regularly. To lighten this burden, you can opt for tools that use automated workflows to get the job done.

Hakim also says that too often, companies think of translation as an afterthought, which means they have a manual process on top of an automated workflow. With Smartling, they can integrate it into their existing approach to streamline the process. It results in a workflow where content flows into a state of readiness for translation. And our end-to-end solution takes care of the translation.

Once the translation is complete, it flows back to the customer’s content creation flow, where they either conduct quality checks or publish directly.

Localize your iOS app with Smartling

iOS app localization is essential for any business seeking to increase its global reach and successfully enter new markets. The process begins with selecting an appropriate set of target languages and then creating a solid go-to-market strategy to launch it in these markets.

It's also vital to keep best practices in mind when localizing, such as ensuring all text strings are externalized from code, and testing should occur throughout the process. With proper planning and execution of these steps, businesses can successfully localize their iOS apps and find success in a wide variety of global markets.

Localization solutions like Smartling can help you manage the entire process using its end-to-end translation management system. You can download the internationalized file from the app and directly input it into our systems to ensure that translations happen on the go. It reduces the turnaround time, improves the localization quality, and helps you launch apps quickly in your target markets.

Ready to localize your iOS app for different target markets? Book a meeting with Smartling to see how we can help you streamline this process.

Watch: Localizing While Staying On Brand with Rover