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LocalASO

Glossary

ASO glossary

Plain definitions of App Store Optimization terms, each with why it matters, an example and Apple's own source where one exists.

A

  • A/B testing (App Store)

    A/B testing compares two versions of a page to see which converts better. What Apple's product page optimization tests and what you must test another way.

  • AI keyword suggestions (ASO)

    AI keyword suggestions are term ideas a language model proposes for your listing. What they do well, why they need real ranking data and how to check them.

  • App Analytics (App Store Connect)

    App Analytics is the App Store Connect area for engagement, campaign and monetization data. What Apple states, thresholds for tests and how ASO uses it.

  • App description (App Store)

    The App Store description is the long text on your product page. What Apple says about its limit, plain text and search, and how to structure it.

  • App icon (App Store)

    The app icon is the first image people see in App Store results. What Apple says about changing it after release and how to test alternate icons.

  • App name (App Store)

    The app name is the title shown on your App Store listing and one of the fields Apple searches. What it is, Apple's rules for it and how to choose one.

  • App preview (App Store video)

    An app preview is a short video on your App Store product page. Apple's length, count and format rules, the guideline and how it differs from screenshots.

  • App privacy details (privacy label)

    App privacy details are the data-collection answers shown on your product page as a privacy label. Apple's definitions, required links and update rules.

  • App Review

    App Review is Apple's check of apps and metadata before release. What Apple says about timing, status, expedited requests and repeat rejections.

  • App Review Guidelines

    The App Review Guidelines are Apple's rules for what can go on the App Store. The sections that matter for metadata: 2.1, 2.3 and 5.1.1.

  • App Store Connect

    App Store Connect is Apple's tool for uploading, submitting and managing apps, including the metadata fields ASO work edits. What it is and what it covers.

  • App Store Connect API

    The App Store Connect API lets tools read and write listing data like names and keywords by locale. What it covers and how it differs from iTunes.

  • App Store search

    App Store search returns apps by text relevance and user behavior. The fields Apple searches, what appears in results and what Apple does not publish.

  • App Store tags (search results)

    App Store tags are labels Apple generates with large language models from your metadata and may show in search. What Apple states and what to do.

  • App version (App Store Connect)

    An app version is a release with its own build and version-level metadata. Which fields belong to a version and which Apple lets you edit freely.

  • Apple Ads (App Store advertising)

    Apple Ads sells App Store placements: Today tab, Search tab, search results and product pages. What each does and how it relates to ASO.

  • ASO (App Store Optimization)

    ASO, or App Store optimization, is improving how your app is found and chosen on the App Store. The two halves, the fields involved and where to start.

  • ASO vs SEO

    ASO optimizes an app listing inside the App Store; SEO optimizes web pages for search engines. The shared ideas, the differences and where the two meet.

B

  • Branded keyword (App Store)

    A branded keyword is a search term containing a brand or app name. Own brand terms are free to rank for; competitor brands are barred by Apple's rules.

  • Byte limit (App Store keyword field)

    The byte limit caps the keyword field at 100 bytes, not characters. Why Apple counts bytes, how many characters that holds per script and how to check it.

C

  • Character limit (App Store metadata)

    A character limit caps how many characters a metadata field accepts. Which App Store fields use characters, which use bytes and why the difference matters.

  • CJK characters (App Store metadata)

    CJK means Chinese, Japanese and Korean text. How these scripts use the 100-byte keyword field, the 3-character keyword minimum and the locale codes.

  • Competitor keyword (ASO)

    A competitor keyword is a term a rival app ranks for. How to learn from them legally, since Apple bars competitor names from your own keyword field.

  • Competitor tracking (ASO)

    Competitor tracking means watching where rival apps rank for your keywords over time. What to follow, what you may reuse and how it shapes your next move.

  • Conversion rate (App Store)

    App Store conversion rate is the share of people who see your app and then download it. How it is defined, what moves it and what Apple's averages say.

  • Custom product pages (App Store)

    Custom product pages are alternate versions of your App Store page, up to 70 per app, with their own screenshots, text and keywords. Rules and uses.

D

  • Dead keyword (ASO)

    A dead keyword has so little search volume that it is not worth a slot in your metadata. How to spot one, free the bytes and avoid false positives.

  • Developer name (App Store)

    The developer name appears under your app name and is searchable as company name. Apple's rules for setting it and why it cannot be edited later.

  • Developer response (App Store reviews)

    A developer response is your public reply to an App Store review. Who can post it, how editing works, what Apple advises and when to report instead.

F

  • First-time downloads (App Analytics)

    A first-time download is a person's first install of your app on a device. How Apple defines it, how it differs from redownloads, and its test thresholds.

G

  • Generic keyword (ASO)

    A generic keyword describes what an app does without a brand name, while Apple also calls words like app and game wasteful. Both meanings explained.

H

  • Head term (ASO)

    A head term is a short, broad, highly searched keyword with strong competition. How it differs from long-tail keywords and when it is worth targeting.

I

  • Impressions (App Analytics)

    Unique impressions count people who see your app icon on the App Store in a day. How Apple defines them, why they set conversion rate, what moves them.

  • In-App Events (App Store)

    In-App Events are time-limited events you promote on the App Store, shown on product pages and in search. Apple's limits for names, length and publishing.

  • iTunes Lookup API

    The iTunes Lookup API returns the public data of an app from its ID. How it differs from the Search API, what Apple says about speed and when to use it.

  • iTunes Search API

    The iTunes Search API is Apple's public endpoint to search the App Store catalog and look up apps by ID. Parameters, rate limit and what it cannot do.

K

  • Keyword (App Store)

    In ASO a keyword is a word or phrase people type into App Store search. Where Apple reads keywords from, how many you can use and how to pick good ones.

  • Keyword cannibalization (App Store)

    Keyword cannibalization is repeating words across your name, subtitle and keyword field. What Apple advises, why it wastes space and how to find it.

  • Keyword difficulty (App Store)

    Keyword difficulty estimates how hard it is to reach the App Store top 10 for a search term. How the score is built, an example and its limits.

  • Keyword field (App Store)

    The keyword field is a hidden, comma-separated App Store Connect field that Apple searches but customers never see. Definition, rules and an example.

  • Keyword gap (ASO)

    A keyword gap is a relevant term where competitors rank and you do not. How to find gaps, filter them honestly and turn the best into metadata changes.

  • Keyword localization (ASO)

    Keyword localization means researching the terms people search in each language, not translating your English list. How it works and why bytes matter.

  • Keyword ranking (App Store)

    A keyword ranking is the position of your app in App Store search results for one term in one country. How it is measured and why it differs by storefront.

  • Keyword research (ASO)

    ASO keyword research finds the search terms to put in your name, subtitle and keyword field. The steps, the data to check and the rules Apple sets.

  • Keyword stuffing (App Store)

    Keyword stuffing means packing metadata with repeated or irrelevant terms. What Apple's Guideline 2.3.7 says, examples and what to do instead.

  • Keyword swap (ASO)

    A keyword swap replaces a term you rank for but nobody searches with a better one. How the Swap verdict works, how to pick the replacement, what to watch.

L

  • Locale (App Store metadata)

    A locale is a language version of your App Store metadata, written as a code like en-US or pt-BR. How App Store Connect uses locales and how to read codes.

  • Locale code (App Store Connect API)

    A locale code is the short identifier, such as en-US or zh-Hans, that the App Store Connect API uses for a metadata language. Format and examples.

  • Localization (App Store)

    App Store localization means writing separate metadata for each language so people can find and understand your app. What can be localized, and the rules.

  • Localization fallback (App Store)

    Localization fallback is what the App Store shows when your listing has no metadata in a user's language. How Apple documents it and what to test yourself.

  • Long-tail keyword (App Store)

    A long-tail keyword is a specific multi-word search with fewer searches and less competition. How it works in the App Store, with examples and trade-offs.

M

  • Mac App Store

    The Mac App Store lists macOS apps. Screenshot sizes, category rules and previews that differ from iPhone listings, plus what LocalASO is and is not.

  • Machine translation (App Store metadata)

    Machine translation turns your listing text into another language by software. Where it helps with App Store metadata, where it fails and how to review it.

  • Marketing URL (App Store)

    The Marketing URL is an optional App Store field that links to your product website. What Apple requires, whether it affects search and how to use it.

  • Metadata rejection (App Review)

    A metadata rejection means App Review refused a submission because of listing text, images or links. The guidelines behind it and a checklist to avoid one.

  • Metadata update (App Store)

    A metadata update changes your listing text or images. How long changes can take to appear, which edit needs a new version and how to measure results.

  • Model Context Protocol (MCP)

    The Model Context Protocol lets AI tools call external tools and read data. What MCP means for ASO and the five tools LocalASO's MCP server exposes.

P

  • Pre-orders (App Store)

    Pre-orders let people order your app before release, with a limited product page that appears in search. Apple’s date windows, regions and notice rules.

  • Primary category (App Store)

    The primary category is the main App Store category you pick. Why Apple indexes it for search, how it differs from the secondary one, and the rules.

  • Primary language (App Store)

    The primary language is the default language of your App Store metadata, used when no localization matches. What Apple says and how to choose it.

  • Product page optimization (App Store)

    Product page optimization is Apple's A/B testing for icons, screenshots and previews. Up to 3 treatments for 90 days. Rules, limits and what to test.

  • Promotional text (App Store)

    Promotional text is an editable line above the App Store description. What it means, what Apple says about search and updates, and what to write in it.

Q

  • Quick-win keyword (ASO)

    A quick-win keyword is a relevant term where you already rank just outside the top 10 and competition is manageable. How to spot one and what to change.

R

  • Rank tracking (App Store)

    Rank tracking records your app's keyword positions over time, by country. What to track, how often, and how to avoid reading noise as progress.

  • Rating count (App Store)

    The rating count is the number of ratings an app has. Why it is the public signal behind most volume and difficulty estimates, and where it falls short.

  • Rating prompt (SKStoreReviewController)

    The rating prompt is the standard in-app dialog that asks users to rate your app. Apple's limit of three prompts in 365 days and when to show it.

  • Ratings (App Store)

    App Store ratings are the 1 to 5 star scores users give an app. How they appear in search, what Apple says about ranking and how tools use rating counts.

  • Ratings reset (App Store)

    A ratings reset clears the overview star rating when you release a new version. What it affects, what it cannot undo and when it might be worth using.

  • Redownloads (App Analytics)

    A redownload is when someone who has installed your app before adds it to a device again. How Apple counts it and how it affects conversion rate.

  • Reviews (App Store)

    App Store reviews are written feedback beyond star ratings. How review summaries work, what a ratings reset leaves untouched and how to respond.

S

  • Screenshots (App Store)

    App Store screenshots are the images on your product page and in search results. Apple's limits, sizes and guideline, plus how they affect conversion.

  • Search popularity (Apple Ads)

    Search popularity is Apple Ads' 1 to 5 indicator of how popular a keyword is in App Store searches. What it measures, what it does not and how to use it.

  • Search results ads (Apple Ads)

    Search results ads show your app when people search the App Store. Keywords, the two bidding strategies Apple offers and how they differ from organic rank.

  • Search volume (App Store)

    Search volume estimates how often people search for a keyword in the App Store. Why Apple publishes no exact counts and how tools estimate demand instead.

  • Secondary category (App Store)

    The secondary category is an optional second category for your app. What Apple says about indexing, how it differs from the primary one and how to choose.

  • Singular and plural keywords (App Store)

    Should you list both habit and habits? Apple advises avoiding plurals of words already included but documents no more. What to know and how to test it.

  • Storefront (App Store)

    A storefront is the App Store of one country or region, with its own rankings and languages. How it differs from a locale, with Apple's numbers.

  • Subtitle (App Store)

    The App Store subtitle is a short line under your app name that is shown across the store and searched by Apple. Definition, rules and a worked example.

  • Support URL (App Store)

    The Support URL is a required App Store field that must lead to real contact information. What Apple requires, how to localize it and what to avoid.

T

  • Text relevance (App Store search)

    Text relevance is how well your metadata matches a search query. Which fields Apple names, what Apple does not document, and how to test relevance.

  • Top 10 ranking (App Store)

    A top 10 ranking means your app is among the first ten search results for a term. Why tools measure it, what Apple shows there and how to reach it.

  • Traffic sources (App Analytics)

    Traffic sources show where downloads come from: App Store Search, Browse, app and web referrers, campaign links. What Apple reports and its thresholds.

  • Transcreation (ASO)

    Transcreation recreates your message for a market instead of translating it word for word. How it applies to App Store names, subtitles and keywords.

U

  • User behavior signals (App Store ranking)

    User behavior signals are the downloads, ratings and reviews Apple says affect search alongside text relevance. What is stated and what is not.

  • UTF-8 (and the keyword field)

    UTF-8 is the encoding that decides how many bytes each character takes. Why it determines how much fits in the 100-byte App Store keyword field.

W