ASO for Multilingual Markets: Keyword Research Beyond Translation
Most app teams treat localization as a translation problem. They take their English keyword list, hand it to a translator, swap in the foreign-language equivalents, and call the metadata done. Then they wonder why their German or Brazilian Portuguese rankings never materialize.
The reason is simple: users don't search in the same conceptual vocabulary across markets. A German fitness app user searching for an interval timer will not type the literal German translation of "interval timer." They might type "Intervalltraining App," or "HIIT Uhr," or "Tabata Timer Deutsch" — each a different keyword with different search volume, different competition, and different conversion intent. Translation gives you none of that.
This guide lays out a repeatable framework for multilingual ASO keyword research — one that treats each market as its own search ecosystem rather than a mirror of your English metadata.
Why Direct Translation Fails in the App Stores
App stores are not translation engines. They're search engines with their own ranking signals, and keyword relevance is evaluated against the actual queries users type in each locale.
When you translate keywords directly, you face three compounding problems:
1. Search volume doesn't transfer. A keyword that drives strong installs in the US may have near-zero search volume in the target market — even if the translation is technically accurate. User habits and vocabulary diverge sharply at the category level.
2. Compound words change keyword density. German is the obvious example. "Fitness tracker" becomes "Fitnesstracker" — one word, not two. Your keyword field strategies need to account for how compounds are indexed versus split terms.
3. Colloquial terms don't translate. Users in Brazil might search for a ride-share app using slang that has no English equivalent. If you've only translated, you'll miss those queries entirely.
The fix isn't more careful translation. It's independent keyword research in each language and market — starting from user behavior, not English source copy.
The Four-Layer Multilingual Keyword Research Framework
Here's the process we use when running app localization keyword research for a new market. It has four layers, and you can't skip any of them.
Layer 1: Seed Keywords From Native Search Behavior
Don't start with your English keywords. Start with the category. Go into the target-market App Store or Google Play, find the top 5–10 apps in your category, and look at their metadata in the native language. What words appear in their titles and subtitles? Those are your seed keywords.
Then take those seeds into App Store Connect's keyword planner (or a third-party ASO tool with locale support) and expand from there. The goal is to surface terms that actual users in that market type — not terms that a bilingual human thinks they would type.
Layer 2: Search Volume and Difficulty Scoring by Locale
Once you have a seed list, score every keyword on two dimensions: search volume in that locale and keyword difficulty (how competitive the term is in that specific storefront). These numbers differ significantly from the global or US equivalents.
A table like this helps keep markets organized:
| Keyword (DE) | English Equivalent | Volume (DE Store) | Difficulty | Priority |
|---|---|---|---|---|
| Fitnesstracker | Fitness tracker | High | High | Long-tail first |
| HIIT Timer App | HIIT Timer App | Medium | Medium | Target now |
| Intervalltraining | Interval training | High | High | Title candidate |
| Tabata Uhr | Tabata clock | Low | Low | Quick win |
| Workout Planer | Workout planner | Medium | Medium | Subtitle candidate |
Run this table for every market you're entering. The priorities will look different in each one.
Layer 3: Intent Mapping — Informational vs. Transactional Search
Not every keyword signals the same user intent. "What is interval training" is informational — that user is researching, not installing. "HIIT Timer App kostenlos" (free) is transactional — that user has their wallet (or finger) out.
App store metadata should be heavily weighted toward transactional and navigational intent. Informational keywords belong in your app's website content or SEO work, not in your 100-character keyword field.
Filtering for intent at this stage saves you from wasting keyword field space on terms that generate impressions but not installs.
Layer 4: Cultural Validation
This layer is where most agency work falls short. Cultural validation means having a fluent native speaker — ideally someone in the target market, not just a bilingual colleague — review the final keyword list for:
- Register: Is the language formal or informal? German app stores lean formal; Brazilian Portuguese often skews casual.
- Connotation: Does a keyword have unintended associations in that market?
- Completeness: Are there high-volume colloquial terms missing that didn't surface in tool-based research?
This isn't a translation review. It's a market sense-check. Budget for it. It's typically a few hours of a native consultant's time and it materially changes conversion rates on the listing.
Structuring Metadata Fields Across Locales
Once you have your keyword lists by market, the next question is where to place them. The rules differ between Apple App Store and Google Play, and they also interact with localization in non-obvious ways.
Apple App Store:
- Title (30 chars): Your single most important keyword should anchor here. Titles are the heaviest ranking signal.
- Subtitle (30 chars): Second-tier keyword. Think of it as a supporting signal.
- Keyword field (100 chars): Hidden from users, indexed by Apple. No spaces around commas, no repeating words already in title or subtitle — Apple doesn't double-count them, and you're wasting characters.
One important note: Apple indexes each locale's metadata independently. Your US English keywords do not help your German rankings. Every locale needs its own fully researched metadata set.
Google Play:
- Title (30 chars): Same weight as Apple.
- Short description (80 chars): Indexed and user-visible. This is your subtitle equivalent.
- Long description (4,000 chars): Google Play indexes the full text. Keyword density matters here in a way it doesn't on Apple. Place your primary and secondary keywords naturally in the first 167 characters (the fold) and distribute supporting terms throughout.
Localization on Google Play also affects your store listing experiments. You can A/B test graphics by locale — which matters because what converts in the US (bold color, feature callouts) often underperforms in markets like Japan, where cleaner, icon-led screenshots typically convert better.
Common Mistakes That Undermine Multilingual ASO
Keyword cannibalization across locales. Some teams create a "Spanish" listing that serves both Mexico and Spain. Search behavior differs enough between those markets that you're leaving ranking potential on the table. Where volume justifies it, create separate locale-specific metadata sets.
Ignoring ratings and reviews in the target language. App store algorithms factor in rating recency and volume by locale. An app with 10,000 US reviews and 12 German reviews will struggle in the German storefront. Build a review solicitation strategy that targets each market, not just your largest one.
Setting and forgetting. Keyword volume and competition shift. A term that was a quick win six months ago may now be high-difficulty. Multilingual ASO metadata needs a quarterly review cycle at minimum.
Over-localizing to the point of brand inconsistency. Your app name and core brand identity should stay consistent. What localizes is the supporting copy and keywords — not the product name, which affects recognition in cross-market marketing campaigns.
For a deeper look at how ASO connects to broader discoverability strategy, our post on deep linking and strategic marketing covers how metadata decisions interact with your paid and organic acquisition funnels.
Prioritizing Markets: Not Every Locale Is Worth Full Investment
Full multilingual ASO research takes time and costs money. Here's a simple prioritization matrix:
| Market Signal | Weight |
|---|---|
| Existing organic installs from that locale | High |
| Paid UA performance in that market | High |
| App Store revenue per download in that region | High |
| Competitor density (lower = easier wins) | Medium |
| Language complexity (unique script, compound words) | Medium — affects execution cost |
Start with markets where you're already getting installs without localized metadata. That's the clearest signal that demand exists — you're just leaving conversions on the table by not meeting users in their native search vocabulary.
Semnexus runs multilingual ASO research and implementation as part of our mobile app marketing services. If you're expanding into a new market and want keyword research done right from the start, that's the engagement to look at.
FAQ
Is app localization the same as ASO localization?
No. App localization typically refers to translating the app's UI, strings, and content for a new market. ASO localization is specifically about optimizing your App Store and Google Play metadata — title, subtitle, keyword fields, screenshots, and description — for each locale's search behavior. You can have a fully localized app with completely unoptimized ASO metadata, and vice versa.
How many characters should I use in Apple's keyword field?
Use all 100. Every unused character is a ranking signal you're leaving behind. Separate terms with commas, no spaces, and don't repeat words already used in your title or subtitle — Apple's algorithm doesn't reward the duplication and you're wasting space.
Do I need separate keyword research for the App Store and Google Play in each market?
Yes. The two storefronts index metadata differently, have different ranking algorithms, and serve user bases with different search habits. What works on the App Store in France won't automatically work on Google Play in France, even in the same language.
How often should I refresh multilingual ASO metadata?
Quarterly is the minimum for active markets. If you're running paid user acquisition in a market, review the keyword metadata monthly — paid performance data often surfaces search terms worth testing in organic metadata.
Can I use the same screenshots across all locales?
You can, but you shouldn't if conversion is the goal. Screenshots are the highest-impact visual element on a store listing. What reads as persuasive in the US — feature callouts with bold typography — often underperforms in markets like Japan or South Korea, where users respond better to clean, icon-forward layouts. Test by locale where volume justifies the production cost.
How do I handle right-to-left languages like Arabic or Hebrew in App Store metadata?
Apple and Google both support RTL rendering in metadata. The character limits are the same. The bigger challenge is keyword research — RTL markets have fewer third-party ASO tool integrations, so you'll rely more heavily on native speaker input and competitor metadata analysis rather than volume data from tools.
Multilingual ASO isn't a translation exercise — it's a full research cycle run separately for every market you care about. The teams that treat it that way consistently outrank the ones that don't, and the install volume difference is measurable.
If you're expanding into new markets and want keyword research done from the ground up — not handed off to a translator — book a call with us or explore our mobile app marketing services to see how we approach ASO for apps in active growth.
