App Store keyword research is the process of identifying which search terms your target users type into the App Store, then strategically placing those terms in your metadata so Apple indexes your app for them. It's the highest-leverage activity in App Store Optimization — and most developers either skip it entirely or do it wrong.
Getting keyword research right determines whether your app appears in front of thousands of relevant users per day or remains invisible to everyone except people who already know your app name. This guide covers how Apple's search indexing works, how to find keywords worth targeting, how to evaluate them, and the placement mistakes that waste your 100 bytes of keyword field.
How App Store Keyword Indexing Actually Works
Before researching keywords, you need to understand what Apple's algorithm indexes. Apple does not index every word in your app description. It indexes three specific metadata fields: your title, your subtitle, and your keyword field. Everything outside those three fields is invisible to search.
Apple also automatically indexes your developer name, your app category, and in-app purchase names. Anything you repeat across these fields wastes space — Apple does not give bonus weight to repeated terms.
The three fields that drive keyword rankings
- Title (30 characters): The highest-weighted field. Keywords in your title rank significantly higher than the same keywords in your keyword field. Every character here is premium real estate. Your app name takes priority, but if you can append a short keyword phrase — "App Name · Keyword Phrase" — it produces a meaningful ranking lift for that term.
- Subtitle (30 characters): The second highest-weighted field. Apple introduced the subtitle specifically as an additional keyword placement surface. Many developers use it for marketing copy that no user ever reads. Use it for your second-highest-priority keyword phrase instead.
- Keyword field (100 bytes): The dedicated keyword input in App Store Connect. Comma-separated, no spaces after commas, no duplicating words from your title or subtitle. Each unique word you add here is indexed as a standalone term and in combination with other words in your metadata.
Understanding this hierarchy changes your entire research approach. The question is not just "what keywords should I target?" but "which keywords are important enough for the title, which for the subtitle, and which for the field?"
How to Find App Store Keywords Worth Targeting
Good keyword research starts with generating a large pool of candidates, then filtering down to the ones that are worth your limited metadata space.
Start with your core function
Write down every way a user might describe what your app does. If you built a habit tracking app, the starting list includes: habit tracker, daily habits, habit builder, streak tracker, routine app, goal tracker, daily routine, productivity tracker. Don't edit yourself at this stage. You want quantity before quality.
Then expand each term into variations: long-tail versions ("habit tracker for iPhone"), problem-framed versions ("build daily habits"), and outcome-framed versions ("streak goals app"). Real users search in all of these patterns. Your job is to match their language, not your own internal vocabulary for what you built.
Mine competitor keywords
The most reliable source of proven keywords is your competitors. If an app similar to yours ranks for a term, that term has real search volume — the ranking is direct evidence of it. Competitor keyword analysis tells you exactly which terms have demand without guessing.
The process: identify your top 3-5 direct competitors in the App Store, then use an ASO tool to see which keywords they rank for. Look for keywords where a competitor ranks in positions 5-20 — those are reachable, have proven demand, and aren't fully locked up. Terms where a competitor ranks #1 with 50,000 reviews are a different challenge.
Use App Store autocomplete
Open the App Store search on any device and start typing your core keywords. The autocomplete suggestions are Apple's real-time data on what users actually search for. These are not guesses — they reflect actual search frequency. Every autocomplete suggestion is a keyword worth adding to your research list. Apple also publishes guidance on how App Store search works for developers who want to understand the indexing model directly.
Check your existing rankings
If your app has any existing downloads, you're already ranking for some keywords — probably not intentionally. An ASO tool like Komori surfaces every keyword your app currently ranks for, including ones you never explicitly targeted. Some of these accidental rankings are in positions 15-30, meaning a metadata update to explicitly include the term could push you into the top 10 with minimal effort.
Research keywords with real App Store data
How to Evaluate App Store Keywords
Once you have a list of 50-100 candidate keywords, you need to filter it down to the 15-20 that will actually fit in your metadata. Two metrics do most of this work: popularity and difficulty.
Popularity: how many people actually search for this
Keyword popularity is a score (typically 0-100) reflecting relative search volume in the App Store. Apple does not publish raw search volume numbers — the data comes from ASO tool providers who estimate it through proprietary methods. The exact numbers vary between tools, but the relative ordering is reliable.
A keyword with a popularity score of 7 is effectively invisible. A keyword with a score of 60+ is actively searched by a meaningful number of users. The sweet spot for most apps is keywords in the 40-70 range: enough volume to matter, but not so high that every major app in your category is targeting it with years of ranking history.
Difficulty: can you actually rank for this
Difficulty measures how entrenched the current top-ranking apps are for a given keyword. A difficulty score of 90 means the top 10 apps all have tens of thousands of reviews, millions of downloads, and years of ranking history. Targeting that term with a new app is not a strategy — it's a waste of 10 characters of your keyword field.
For new apps, target keywords with difficulty below 40. For established apps with 1,000+ reviews, you can compete for difficulty 40-65. High-difficulty terms (65+) are generally only worth targeting if you already have category authority.
Relevance: will these users actually download your app
A keyword can have high popularity and low difficulty and still be wrong for your app. Ranking for "free games" when you built a productivity tool produces impressions but no conversions. The user's intent doesn't match what you offer, so they scroll past immediately.
Always ask: if a user searching for this keyword finds my app, will they download it? High install-to-impression conversion rate is a positive ranking signal. Low conversion signals irrelevance and actively hurts your visibility. Targeting irrelevant keywords to inflate impressions is counterproductive.
Placing Keywords Without Wasting Space
With 100 bytes in the keyword field plus 30 characters each in your title and subtitle, you have roughly 160 characters of indexed metadata to work with. Every character that doesn't contribute a unique, valuable keyword is a wasted opportunity.
Rules that maximize coverage
- No spaces after commas. "habit,tracker" uses 13 bytes. "habit, tracker" uses 14 bytes. At scale, spaces waste 5-10 characters you could use for an extra keyword.
- No words repeated from title or subtitle. If "habit" is already in your title, putting "habit" in the keyword field adds zero coverage. Apple indexes the word once regardless of how many fields it appears in.
- Singular vs. plural — pick one. Apple typically indexes both forms when it encounters either. You don't need "habit,habits" — use the byte for a different keyword.
- No articles, prepositions, or stop words unless absolutely required to form a meaningful phrase. Apple ignores most of them anyway. "for,the,and,to" is four bytes of nothing.
- Keywords combine across fields. If your title contains "habit" and your keyword field contains "tracker", Apple indexes the combination "habit tracker" even though neither field contains the full phrase. Build your keyword strategy around this combinatorial logic to cover more terms with fewer characters.
Use our App Store metadata counter to track your byte usage in real time as you build out your keyword field.
Keyword Research Mistakes Most Developers Make
After analyzing thousands of App Store listings, the same errors appear repeatedly. Avoiding them is worth more than any advanced tactic.
Targeting only obvious, high-competition terms
Every developer building a fitness app targets "fitness" and "workout." Those terms have difficulty scores above 80. You will not rank for them with a new app. Meanwhile, "hiit timer app" or "bodyweight workout no equipment" have meaningful volume and difficulty scores a new app can compete for. The unsexy long-tail keyword that 3,000 people search for per month and you rank #2 for is more valuable than a high-volume term you rank #150 for.
Never revisiting the keyword field after launch
App Store search trends shift. New terms emerge as user behavior evolves. Competitor apps enter and exit. Your own rankings change as you accumulate reviews and history. A keyword set that was optimal at launch will drift out of alignment with reality within 6 months.
Set a calendar reminder to audit your keywords every 4-6 weeks. Use rank tracking data to identify which terms you've moved up or down on, drop the ones you're not ranking for after 8+ weeks with no movement, and test replacements.
Ignoring localization as a keyword multiplier
Each App Store locale has its own independent keyword field. An app localized into French, German, and Spanish has three additional 100-byte keyword fields to work with. Users in those markets search in their own language, and the competition for non-English App Store keywords is dramatically lower than for English equivalents.
Developers who localize their metadata consistently report significant organic install growth from non-English storefronts, often matching or exceeding their English-language downloads. See our comparison of the best ASO tools in 2026 for options that support multi-locale keyword research.
Using competitor brand names
Apple's App Store Review Guidelines (Section 5.2) prohibit using third-party brand names in your metadata without authorization. Beyond the policy risk, it rarely converts. Someone searching for a specific competitor app is not looking for an alternative — they're looking for that app. Your conversion rate from branded competitor keywords is low enough that the slots are better used on terms where users have genuine open intent.
Frequently Asked Questions
How many keywords can you add to the App Store keyword field?
Apple's keyword field allows 100 bytes per language. That's roughly 15-20 individual keywords depending on word length. You should not use spaces after commas, repeat words that already appear in your title or subtitle, or include your app name — Apple indexes those automatically.
What makes a good App Store keyword?
A good App Store keyword has meaningful search volume, manageable competition, and high relevance to your app's core function. The ideal keyword is one your competitors rank for but haven't fully dominated — proving demand exists while leaving room for you to rank.
How often should you update your App Store keywords?
Review your keyword set every 4-6 weeks. Track which keywords you're ranking for, drop terms where you rank below position 20 with no upward movement after 8+ weeks, and test replacements. Major metadata changes should be batched into app updates to minimize review cycles.
Should you use competitor names as App Store keywords?
No. Apple's guidelines prohibit using competitor brand names in your keyword field. Beyond the policy risk, branded keyword traffic converts poorly — users searching for a specific competitor aren't looking for an alternative. Use the bytes for high-intent, open-category terms instead.
The Bottom Line on App Store Keyword Research
App Store keyword research is not a one-time setup task. It is an ongoing process of identifying high-value search terms, placing them efficiently across your title, subtitle, and keyword field, tracking what ranks and what doesn't, and iterating based on real data. Developers who treat it this way consistently grow their organic installs without touching their ad spend.
The mechanics are learnable. The data is accessible. The competitive advantage goes to whoever is most systematic about it — because most developers still do it once at launch and never revisit it.
Komori is a native macOS ASO tool that makes this process practical: 45M+ keywords with real popularity and difficulty scores, unlimited rank tracking, competitor gap analysis, and a keyword field editor that shows your byte count in real time. Everything you need to turn app store keyword research from a guessing game into a repeatable growth system.
Browse our free ASO tools to start optimizing without spending a cent.