Apple gives every app 50 localizations, each with its own title, subtitle and keyword field. An English-only app fills in one. Every other one is a market searching in its own words for an app it cannot find.
A listing is not a country. English (U.K.) is the listing for 172 storefronts and Japanese for one, while the US store alone reads ten.
The short version
If you read nothing else.
01
Map storefronts to listings first
Know which stores read each localization before you write a word.
02
Research, do not translate, the keywords
Use what people type in that store.
03
Fill all 160 search characters
Title, subtitle and keyword field, in every language.
04
Copy the required fields
Description, support URL and privacy URL, or the version will not submit.
05
Use the extra listings your store reads
The US store reads ten.
A storefront and a language are not the same thing
Apple maps every App Store storefront onto 50 localizations, and the map is uneven. Japanese is the listing for one storefront. German covers four. English (U.K.) covers 172. Edit one localization and every storefront that reads it changes at once.
It also runs the other way. One storefront can read several localizations, and the US store reads ten: English (U.S.), Spanish (Mexico), French, Arabic, both Chinese scripts, Russian, Korean, Portuguese (Brazil) and Vietnamese. Each is its own title, subtitle and 100-character keyword field.
Anywhere your app has no listing in a language, Apple shows your primary language instead. Your app is still there. It is just being shown in words most of that country does not search in.
Demand is per storefront. The characters you write are per localization. Plan with both.
Translate the meaning, then research the words
A correct translation is not the same as a good keyword. The phrase someone types in Germany for a plant identifier app is "pflanzen bestimmen", to identify plants, not a word-for-word version of "plant identifier". Translated literally, your listing reads fine and matches nobody.
So treat each language like a new launch. Start from the job your app does, look at what that store's search suggestions offer when you type it, and check which of those phrases people actually search. Then write the title, subtitle and keyword field around the strongest one.
The description is different. It is there to convince, not to be matched, so a careful translation checked by a native speaker is the right tool for it.
Translate the description. Research the title, subtitle and keywords.
Pick the languages that pay back first
Start where you already sell. Your App Store Connect sales by country show where people find you in English and would find you more often in their own language.
Then look at reach. French is the listing for 32 storefronts, Spanish (Mexico) for 19 and Arabic for 17, so one good listing in each covers a lot of the map. Japanese, Korean and German each serve one or a few storefronts, but those are some of the highest-spending App Stores there are.
Finally, fill in the extra listings your home store already reads. For an app selling in the US, Spanish (Mexico) reaches the tens of millions of Americans who speak Spanish, and it is one more title, subtitle and keyword field in the store you care about most.
Worldwide in ASO Studio. Each country by demand and how much of it you capture, and the market to write for next.
What to fill in, and what Apple requires
Search runs on the title, subtitle and keyword field, so write those first, all 30, 30 and 100 characters of them. A localization with a strong title and an empty keyword field is leaving most of its reach unused.
Before a version with a new localization can be submitted, Apple also needs a description, a support URL and a privacy policy URL in it. Copy them from your primary language to start, then translate the description when you can.
Screenshots can wait. Apple shows your primary language's screenshots until you add local ones. When you do, translate the captions first: they are what a visitor reads before deciding to download.
A new localization goes out with your next version, like any other listing change.
Measure each language after it ships
A localization is a bet on a market, so check whether it paid. Track your rank on the local searches you targeted in that storefront, and compare downloads from that country before and after the version that added it.
Give it a few weeks. Rankings move after a version is approved and indexed, and a new listing needs time to collect the downloads that hold its place.
Every storefront, grouped by the listing it shows, with your rank, the demand and the market's size in each.
What people ask
Questions.
How many languages can an App Store listing have?
50 localizations.
App Store Connect offers 50 localizations for your listing, each with its own name, subtitle, keyword field, description and screenshots. Your app is available in every storefront you choose either way. Localizations decide which words each storefront shows and searches.
Does localizing my App Store listing increase downloads?
It lets you appear for searches made in that language, and it turns more visitors into downloads, because people install apps whose listing they can read. How much it adds depends on the demand in that storefront, which is why the research comes before the writing.
Should I use machine translation for my App Store listing?
For the description, a good translation checked by a native speaker works well. For the title, subtitle and keywords, start from what people search in that storefront instead, because a correct translation can still be a phrase nobody types.
Do I have to localize the app itself first?
No. You can localize the listing without localizing the app. Say clearly in the description which languages the app supports, so nobody downloads expecting a translation that is not there.
Can I add a localization to an app that is already live?
Yes. Add the language in App Store Connect, fill in its fields, and it goes out with your next version. If you remove one later, those countries go back to showing your primary language.
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