App Store cross-localization: more keyword space in every country

If you only fill in the English (U.S.) listing, your app is searchable through about 160 characters of text in the US: a 30-character name, a 30-character subtitle and a 100-character keyword field. Most indie developers stop there. But the App Store doesn't index just one listing per country. It indexes several, and the extra ones are sitting empty.

#How cross-localization works

Apple defines a set of localizations you can add to your app: English (U.S.), English (U.K.), Spanish (Mexico), French, German and so on. Each one has its own name, subtitle, keyword field, description and screenshots.

Each App Store country (storefront) then indexes a fixed set of those localizations: a primary one and, for most countries, one or more additional ones. When someone searches in that country, the App Store matches the search against the text of all indexed localizations. Which localization a user sees depends on their device language, but which localizations count for search is fixed per country.

So a US user searching in English can find your app through words that only appear in your Spanish (Mexico) keyword field. That is cross-localization.

#Which localizations each country indexes

Apple doesn't publish this mapping. The table below combines two independent public tests, by AppTweak (updated November 2025) and aso.dev (updated October 2026), which agree wherever both cover a country. We verified the Finland row ourselves with Fledly's rank tracking in October 2026.

Two patterns stand out:

• English (U.K.) is the "second listing" of most of Europe and Latin America. If your only English listing is English (U.S.), that is what users in those countries see, but our Finland test showed that the U.S. keyword field was not what ranked us there. Once we added English (U.K.), its keyword field was.
• The US store reads nine extra localizations. That is up to 9 × 160 extra characters, although in practice one or two well-chosen extra keyword fields are enough.

#How to use it without hurting conversion

Users whose device language matches a localization see that localization's name, subtitle and screenshots. That is the risk: if you stuff English keywords into your Spanish (Mexico) title, Spanish-speaking iPhone users in the US and Mexico see a strange English title.

The keyword field has no such risk. It is never shown to users. So the safe pattern is:

1. Title and subtitle stay true to the localization. Spanish (Mexico) gets a Spanish title and subtitle, or simply the same brand name and a short Spanish subtitle.
2. The keyword field holds words for the country where you want to rank. For the US, that is extra English words in the Spanish (Mexico) keyword field. For Germany, it can be German words in the English (U.K.) keyword field, which also counts in France, Sweden, Finland and the rest of the countries that index U.K. English.
3. Don't repeat words across localizations that are indexed in the same country, unless a phrase needs it (see below). A word already in your U.S. keyword field gains nothing by appearing again on its own in the Spanish (Mexico) one.

#Keywords are not combined across localizations

The App Store combines words within a localization: a word in your title and another in your keyword field can form a two-word search. It does not combine words across localizations. If you want to rank for meal planner, both words need to be in the same localization, for example both in the English (U.S.) fields, or both in the Spanish (Mexico) keyword field.

Plan the extra fields as separate keyword groups: each one should hold complete phrases on its own.

#A worked example

Say you have a habit-tracking app with this English (U.S.) listing:

• Name: Tallyday: Habit Tracker
• Subtitle: Daily routine & goal planner
• Keyword field: 100 characters of your best supporting words

To add US reach, you add a Spanish (Mexico) localization:

• Name: Tallyday: Hábitos diarios (honest for Spanish speakers)
• Subtitle: Rutinas y metas (honest for Spanish speakers)
• Keyword field: streak,checklist,reminder,journal,mood,sleep,water,focus,productivity,self care (English words for US searches that didn't fit the U.S. field)

US searchers can now find Tallyday through combinations inside the extra field, such as mood journal, water reminder or sleep journal, while Spanish-speaking users see a correct Spanish listing.

One catch: habit journal still won't match, because habit lives in the U.S. title and journal in the Spanish (Mexico) field. If that phrase matters, add habit to the Spanish (Mexico) keyword field as well. This is the one case where repeating a word across localizations pays off.

To reach Europe, the English (U.K.) localization does the same job for Germany, France, the Nordics, the Netherlands and others: an English title and subtitle (U.K. spelling), and a keyword field with the English words you most want to rank for in those countries.

#Mistakes we see most often

• Only an English (U.S.) listing, outside the US. In much of Europe your U.S. text is what users see, but the U.K. localization is what gets indexed. Add English (U.K.) even if it is a copy.
• Machine-translating the keyword field. A literal translation is rarely what people type. Check the country's autocomplete suggestions and popular searches instead.
• Splitting phrases across localizations. See above: they won't combine.
• Stuffing visible fields. Mixed-language titles look like spam to users and to App Review. Apple's view of mixing languages isn't documented, and AppTweak notes the practice is "frowned upon" even though no rejections have been publicized. Keep the experiment in the invisible field.
• Never verifying. The mapping has changed over the years. After adding a localization, track a few words that exist only in the new keyword field. If you start ranking for them within a week or two, the localization is indexed in that country.

#Frequently asked questions

#What is cross-localization on the App Store?

It is the practice of using a localization that a country indexes in addition to its primary one, for example Spanish (Mexico) in the United States, to add keywords for that country. Each indexed localization has its own name, subtitle and 100-character keyword field.

#Which localizations does the US App Store index?

According to public tests by AppTweak and aso.dev, the US store indexes English (U.S.) plus Spanish (Mexico), Arabic, Chinese (Simplified), Chinese (Traditional), French, Korean, Portuguese (Brazil), Russian and Vietnamese.

#Which localization is indexed in Germany, France or the Nordic countries?

Their own language plus English (U.K.), according to the same tests. We verified the Finland case ourselves in October 2026: Finland indexes Finnish and English (U.K.), not English (U.S.).

#Are keywords combined across localizations?

No. Words are combined within one localization (title, subtitle and keyword field), but not across localizations. Keep both words of a phrase in the same localization.

#Will Apple reject my app for cross-localization?

Using the keyword field of an extra localization is common and we know of no public rejections for it. Putting another language in visible fields like the title is riskier, both with App Review and with users who see that localization.

#Sources

• AppTweak: App Store Localization: Primary and Secondary Languages, published March 2023, updated November 21, 2025.
• aso.dev: Cross-localization, updated October 24, 2026.
• Fledly rank tracking in the Finnish App Store, October 2026.