Keyword Research

Definition

Keyword Research is the systematic process of discovering, evaluating, and selecting the keywords and phrases that users type into app store search bars when looking for apps. It's the foundational activity of Search Optimization — without quality keyword research, all subsequent metadata optimization is guesswork. The output of keyword research is a prioritized keyword list mapped to specific metadata fields (App Title, Subtitle, Keyword Field, Short Description, Full Description).

How It Works

The keyword research pipeline:

Seed Generation → Expansion → Evaluation → Prioritization → Mapping → Monitoring

Step 1: Seed Generation

Start with 10-20 seed keywords from:

• App's core features and use cases
• How users describe the problem the app solves (user language, not developer language)
• Competitor titles and subtitles
• Category browsing terms

Step 2: Expansion

Expand seeds into 200-500 candidates using:

• Autocomplete Suggestions — type each seed in the store, note suggestions. Alphabet expansion ("seed a," "seed b"..."seed z") yields 200+ variations per seed
• Competitor metadata analysis — extract keywords from top 10 competitors' visible metadata
• Search Ads Intelligence — Apple Search Ads Discovery campaigns reveal keywords competitors rank for
• ASO tools — AppTweak, Sensor Tower, MobileAction generate keyword suggestions via AI/semantic clustering
• Google Trends — identify trending and seasonal keywords

Step 3: Evaluation

Score each keyword on:

• Search Volume — estimated monthly searches (Apple Search Ads Popularity 5-100 scale; tool estimates for Google)
• Keyword Difficulty — competitive intensity (how strong are currently-ranking apps?)
• Keyword Relevance — how well does the keyword match your app's actual function?
• Conversion intent — transactional ("best photo editor app") vs. informational ("what is photo editing")

Step 4: Prioritization

Score and rank keywords using a composite formula:

Priority Score = (Relevance × 0.35) + (Volume × 0.25) + (Inverse_Difficulty × 0.25) + (Intent × 0.15)

Step 5: Mapping

Assign keywords to metadata fields by priority:

Step 6: Monitoring & Iteration

• Track keyword rankings daily/weekly
• Re-evaluate keywords monthly
• Replace underperforming keywords (ranked #50+) with new candidates
• Adjust for seasonal trends

Formulas & Metrics

Keyword Opportunity Score:

Opportunity = (Volume / 100) × (100 - Difficulty) / 100 × Relevance_Score

Research coverage check:

Coverage = Keywords_in_Top10 / Total_Keywords_Targeted × 100%

Target: >40% in top 10 after 3 months of optimization.

Keyword field efficiency:

Field_Efficiency = Unique_Keywords / Characters_Used

Best Practices

1. Research is ongoing, not one-time — market dynamics, seasonal trends, and competitor strategies shift constantly. Schedule monthly research sprints.

1. Use 2+ tools for cross-validation — different tools use different estimation methods. Cross-checking prevents over-reliance on one data source.

1. Think like a user, not a developer — users search "step counter" not "pedometer app with accelerometer data." Research user language through reviews and support tickets.

1. Balance head and long-tail — high-volume keywords for visibility; Long-tail Keywords for conversion and achievable rankings.

1. Minimum viable search volume — keywords below ~20 Apple Search Ads Popularity score are unlikely to drive meaningful traffic. Don't waste metadata space on zero-volume terms.

1. September 2025 SAP recalibration — Apple Search Ads Popularity scores dropped 77.4% across the board (algorithmic rebuild). Historical SAP data pre-September 2025 is not directly comparable to current scores.

Dependencies

Influences (this term affects)

• Search Optimization — research output drives all search optimization decisions
• App Title — research determines which keywords go in the title
• Subtitle / Short Description — research informs secondary keyword selection
• Keyword Field — research determines keyword field contents
• Full Description — research guides Google Play description keyword integration
• Search Visibility — quality of research directly impacts keyword coverage

Depends On (affected by)

• Search Volume — volume data is a primary evaluation criterion
• Keyword Difficulty — difficulty assessment informs achievability
• Keyword Relevance — relevance scoring filters irrelevant keywords
• Autocomplete Suggestions — primary expansion source
• Competitive ASO — competitor keywords inform research
• Search Ads Intelligence — Apple Search Ads data enhances research

Related Terms

• Keyword Ranking
• Keyword Relevance
• Search Volume
• Keyword Difficulty
• Long-tail Keywords
• Autocomplete Suggestions
• Metadata Optimization
• Search Ads Intelligence

Sources & Further Reading

• AppTweak: Keyword Research Guide
• ASO World: Complete Keyword Research Checklist (2026)
• Stormy AI: iOS Keywords Playbook (2025)