The Best Languages to Localize Your App in 2025

Choosing Your Localization Markets

With 40+ App Store locales available, where should you focus? This guide covers the best languages to localize iOS app 2025, backed by market data and practical ROI considerations.

Tier 1: Highest ROI Markets

These markets consistently deliver the best return on localization investment.

German (de-DE)

Why it's essential:

• Largest App Store market in Europe
• High purchasing power—German users spend well
• Strong preference for native language content
• Less competition than English for most categories

Characteristics:

• Text runs ~30% longer than English (plan for expansion)
• Formal tone preferred in business apps
• Quality expectations are high

Best for: Productivity, business, utilities, finance apps

Japanese (ja)

Why it's essential:

• Second-largest App Store market by revenue
• Highest spending per user globally
• Users strongly prefer native language
• Enormous mobile-first culture

Characteristics:

• Text is more compact than English
• Cultural adaptation essential (not just translation)
• High quality bar—poor localization backfires

Best for: Games, lifestyle, entertainment, utilities

French (fr-FR)

Why it's essential:

• Large European market with high engagement
• Also covers French-speaking Africa (growing market)
• Strong cultural preference for French content
• Gateway to multiple territories

Characteristics:

• Text runs slightly longer than English
• Formal/informal tone matters by context
• Canadian French (fr-CA) is a useful addition

Best for: Lifestyle, education, health, entertainment

Spanish (es-ES, es-MX)

Why it's essential:

• Massive combined reach: Spain + Latin America
• Growing App Store presence in Mexico and South America
• Lower competition than top-tier markets
• Good ROI for localization investment

Characteristics:

• Regional variants differ significantly
• es-MX (Mexico) often higher volume than es-ES (Spain)
• Consider localizing both separately

Best for: Social, entertainment, utilities, games

Tier 2: Strong Growth Markets

High potential markets that warrant investment after Tier 1.

Portuguese Brazilian (pt-BR)

Why to consider:

• Brazil is a massive mobile market (200M+ population)
• Growing middle class with increasing app spending
• Less saturated than European markets
• Strong ROI potential

Note: pt-PT (Portugal) is different—prioritize pt-BR for volume.

Korean (ko)

Why to consider:

• Tech-savvy, high-spending user base
• Mobile-first culture
• Gaming and entertainment apps perform exceptionally
• Relatively straightforward localization

Chinese Simplified (zh-Hans)

Why to consider:

• Enormous potential market
• High engagement with quality apps
• Growing international app acceptance

Note: Chinese market has unique dynamics—research your category's specific opportunity.

Italian (it)

Why to consider:

• Underserved by many developers
• Good spending power
• European market accessibility
• Lower competition in many categories

Tier 3: Volume & Expansion

These markets extend reach when you've covered the essentials.

Dutch (nl-NL)

Strong purchasing power, often overlooked, English-fluent but prefers native.

Swedish (sv), Norwegian (no), Danish (da)

Nordic markets with high spending but smaller population. Good for specific categories.

Polish (pl)

Large Eastern European market with growing app spending.

Russian (ru)

Significant market size, though payment dynamics differ.

Turkish (tr)

Young, mobile-first population with growing economy.

Quick Win: English Variants

Before tackling new languages, capture English-speaking markets:

English UK (en-GB)

• Different spelling (colour, organise)
• Different terminology (post code, mobile)
• High-spending market with zero translation needed

English Australia (en-AU)

• Similar to UK spellings
• High iOS market share
• Valuable market, minimal effort

English Canada (en-CA)

• Blends US and UK conventions
• Worth including with en-GB update

These variants require minimal changes for meaningful market expansion.

Market Selection Framework

Use this framework to prioritize:

Factor 1: Revenue Potential

• What's the App Store revenue in this market?
• Does your app category perform well there?
• What's the average revenue per user?

Factor 2: Competition Level

• How saturated is your category in this market?
• Can you realistically rank for target keywords?
• What's the quality of existing localized apps?

Factor 3: Localization Complexity

• How different is the language from English?
• Are there cultural considerations?
• Can you access quality localization resources?

Factor 4: Your Current Presence

• Do you have organic traffic from this market?
• Are there support requests in this language?
• Is there competitor pressure in this market?

2025 Market Trends

Emerging Opportunities

India (Hindi, English):

Fast-growing market with increasing spending. English reaches many users, but Hindi localization differentiates.

Indonesia (id):

Massive population, growing smartphone penetration, lower competition.

Vietnam (vi):

Young population, mobile-first, gaming and entertainment strong.

Maturing Markets

Japan, Korea: Already essential; competition is increasing. Quality is the differentiator.

Germany, France: Established value; continuous optimization matters.

Recommended Expansion Path

Phase 1: Quick Wins

• en-GB, en-AU, en-CA
• Minimal effort, immediate expansion

Phase 2: High-Value Markets

• de-DE (German)
• ja (Japanese)
• fr-FR (French)

Phase 3: Strategic Growth

• es-ES and es-MX (Spanish)
• pt-BR (Brazilian Portuguese)
• ko (Korean)

Phase 4: Market Extension

• it (Italian)
• zh-Hans (Chinese Simplified)
• nl-NL (Dutch)
• Additional markets based on data

The Data-Driven Approach

Don't guess—use data:

• **Check your analytics** - Where is your organic traffic?
• **Research competitors** - Which markets are they in?
• **Test with ads** - Run small campaigns in potential markets
• **Start small, validate** - Localize one new market, measure, expand

Making the Decision

For most apps in 2025, the best languages to localize iOS app are:

Must-have: German, Japanese, French, Spanish

High-value: Brazilian Portuguese, Korean, Italian

Smart additions: English variants, Chinese (if category fits)

The specific order depends on your app category, existing traction, and resources. But these languages represent the bulk of international App Store opportunity.

Start where the data points, measure rigorously, and expand based on results. Localization compounds over time—each market you crack opens more opportunity.