Your App Store keyword field is 100 characters. If you only support English, that is your entire ranking surface.
Add German and you get another 100 characters — a completely separate keyword field, indexed independently in its own App Store market. Add French and you get a third. Three locales equals 300 characters of keyword field capacity, each operating in parallel without interfering with the others.
Most indie iOS developers stop at English. They spend weeks trying to squeeze more value out of 100 characters while 200 more characters sit unused in markets where the same users are searching for the same apps.
How locale keyword fields work
The App Store indexes keyword metadata per locale, not per app. Each locale you support has its own independent set:
- Title: 30 characters
- Subtitle: 30 characters
- Keyword field: 100 characters
These fields are indexed separately in each regional App Store. A keyword in your German locale does not reinforce or compete with your English keyword field. They are distinct ranking surfaces in distinct markets.
This means your German locale is not only about reaching German speakers. It is 100 more characters to rank for entirely different terms in the German App Store, at whatever difficulty level that market presents — which is almost always lower than the US.
The compound math
Three locales give you:
- 300 characters of keyword field
- 90 characters of subtitle space
- 90 characters of title space
If you research and fill each locale’s keyword field with terms specific to that market, you can pursue different keyword clusters in three separate app stores simultaneously. Each 21-day testing cycle applies independently. A keyword that fails to move in English can succeed in German without affecting your English ASO work at all.
The US App Store is the most competitive market in the world. It has the highest average keyword difficulty and the most apps chasing the same terms. The German, French, Spanish, and Japanese markets frequently offer the same user intent at a fraction of the competition.
An indie habit tracker that cannot reach the first page in English for “habit tracker” (difficulty 95 in the US) can rank top 5 in German for the equivalent term at difficulty below 50. The users searching are real. The intent is identical. The competition is not.
What good localization adds to keyword strategy
Most ASO guides treat localization as translation work: you write your English copy, translate it, and ship. This framing misses the compound value.
The more useful frame is treating each locale’s keyword field as a separate keyword research project:
For your primary locale (usually English): Fill the keyword field with the best-fit terms you can actually compete for given your app’s current authority. Do not duplicate anything in your title or subtitle.
For secondary locales (German, French, Spanish, Italian): Research what terms users in that market search. The keyword field should reflect local search behavior, not a word-for-word translation of your English terms. Apple indexes each locale’s field independently, so overlap between locales does not help or hurt either one.
For Asian markets (Japanese, Korean, Simplified Chinese): Search competition in many app categories is substantially lower than in English-language markets. Terms that are unattainable in English due to established competitors can be available in top-10 range in these markets for the equivalent concept. This is one of the most underused expansion paths for indie iOS apps.
Marteso’s keyword tracking surfaces rank data per country, so you can see movement in each locale independently. When your German keyword field starts producing rankings, it shows up in the same dashboard as your English tracking — one view, all markets.
The “I do not speak German” objection
Most indie developers skip localization because they assume the translation work is too much. This concern is understandable but overstated for metadata specifically.
App Store metadata — title, subtitle, keyword field, and description — is structured, short copy. Auto-translate handles the mechanical work accurately for all major languages. Your actual effort is reviewing the keyword field: confirming that translated terms are terms users actually search in that market, rather than literal translations of your English keywords that no one types.
Marteso’s auto-translate generates a complete localized metadata set the moment you add a language to your app version. The keyword field benefits from a 10-to-15-minute review against real search data for that market — but the skeleton is there immediately, not built from scratch.
The translation question for description and promotional text is worth more attention. But for the keyword field — the highest-leverage metadata for search ranking — you need 15 minutes of review, not a professional translator.
What to do this week
If your app currently supports only English:
- Pick one language with real search intent in your category. German and French are strong starting points for European markets; Spanish reaches a large US and Latin American audience that often searches in Spanish first.
- Add that locale in App Store Connect, or in Marteso’s version management if you use it.
- Research 10 to 15 terms with real volume and realistic difficulty for your app’s current authority. Competitor keyword fields, your own user language in reviews, and keyword discovery tools are all valid starting points.
- Fill the keyword field with unique terms specific to that locale. Do not copy your English keyword field verbatim — you gain nothing from duplicating terms across locales.
- Run one 21-day cycle and measure rank movement in that market.
One well-researched locale added correctly is a second keyword surface running in parallel with your English ASO work. It does not slow down your existing cycles. It runs alongside them.
Marteso tracks keyword rankings across every locale your app supports. When a new market starts producing movement, you see it immediately alongside your English data — one view, all markets. Start tracking at app.marteso.com.