App Store Optimization Glossary

Clear definitions of every term that matters in App Store keyword research — from keyword popularity and difficulty to storefronts, metadata fields, and competitor teardowns.

All glossary terms

App Store AlgorithmThe App Store algorithm is Apple's automated system for ranking apps in search results — combining metadata relevance, user engagement signals, and quality indicators to determine which apps appear for each search query.
App Store CategoriesApp Store categories are the classifications Apple uses to group apps in browse and featured views — category selection affects both discoverability in browse and how the search algorithm interprets keyword relevance.
App Store Metadata FieldsApp Store metadata fields are the text inputs that affect how an app is discovered and presented in the App Store — primarily the name, subtitle, keyword field, and developer name, each with different character limits and ranking weight.
App Store Optimization (ASO)App Store Optimization is the process of improving an app's visibility in App Store search results and its conversion rate from search impressions to installs.
App Store Search Ranking FactorsApp Store search ranking factors are the signals Apple's algorithm uses to determine which apps appear at the top of results for a given keyword — primarily metadata relevance, user engagement, and app quality indicators.
App Store StorefrontAn App Store storefront is one country-specific instance of the App Store, each with its own search demand, ranking results, and keyword difficulty — 109 storefronts exist in total.
Apple Search AdsApple Search Ads is Apple's paid advertising platform for the App Store, allowing developers to bid on keywords to display their app at the top of search results.
ASO A/B TestingASO A/B testing (also called product page optimization) is the practice of testing alternative versions of app store creative elements — icons, screenshots, descriptions — to improve conversion from search impression to install.
ASO AuditAn ASO audit is a structured review of an app's current metadata, keyword coverage, competitive position, and store presence to identify gaps and improvement opportunities.
ASO Keyword ResearchASO keyword research is the systematic process of identifying, scoring, and selecting the App Store keywords most likely to deliver organic installs given your app's current competitive position.
Branded vs. Non-Branded KeywordsBranded keywords include an app or company name; non-branded keywords describe a problem or category without naming a specific product — the distinction matters for measuring organic discovery versus brand recall.
Burst CampaignsA burst campaign is a short, high-intensity user acquisition push designed to generate enough installs in a brief window to boost an app's ranking for target keywords, leveraging the ranking algorithm's sensitivity to install velocity.
Competing Apps CountThe competing apps count is the number of apps that appear in search results for a given keyword in a specific storefront — a proxy for how saturated that keyword's search results are.
Competitor TeardownA competitor teardown in ASO is the process of identifying which keywords a competing app ranks for — revealing their strategy and surfacing terms you may have missed.
Feature Graphic / Preview Assets (ASO)Preview assets — screenshots and app preview videos — are the visual elements that appear in search results and product pages, directly affecting the conversion rate from impression to install.
In-App Purchase KeywordsIn-App Purchase (IAP) names and descriptions are indexed by Apple for search — giving apps an additional, often overlooked, source of keyword coverage beyond the main metadata fields.
Keyword CannibalizationKeyword cannibalization in ASO occurs when an app's multiple metadata fields target the same keyword, wasting limited character space rather than covering additional search terms.
Keyword DifficultyKeyword difficulty is a 0–100 score estimating how hard it is to break into the top-ranking positions for a given App Store keyword, based on the strength of apps currently holding those positions.
Keyword Gap AnalysisA keyword gap analysis identifies terms that competitors rank for but your app does not — surfacing targeting opportunities you haven't yet captured.
Keyword PopularityKeyword popularity is a 0–100 score measuring how often users search for a given term in the App Store, derived from Apple Search Ads demand signals.
Keyword SeasonalityKeyword seasonality describes the predictable rise and fall of search demand for certain App Store keywords based on time of year, events, or cyclical patterns.
Localization (ASO)ASO localization is the process of writing separate app metadata (name, subtitle, keyword field) in the local language of each target App Store storefront to capture search demand that English-only metadata misses.
Long-Tail KeywordsLong-tail keywords are multi-word, specific search phrases that individually have lower search volume than broad terms but collectively cover the majority of App Store searches and often have much lower ranking difficulty.
Niche KeywordsNiche keywords are terms specific enough to describe a well-defined subset of App Store users — they have moderate-to-low popularity scores but often dramatically lower difficulty than the broad category terms.
Ratings and Reviews (ASO Impact)App Store ratings and review count are quality signals that influence search ranking — higher rating counts correlate with higher ranking for competitive keywords, independent of rating score alone.
Title vs. Subtitle KeywordsIn App Store Optimization, keywords in the app title carry the highest ranking weight; subtitle keywords carry secondary weight — both are more impactful than the keyword field.

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Score App Store keywords by popularity and difficulty across 109 storefronts — the two numbers behind every definition in this glossary.

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