Free ASO Keyword Research Tool

App Store Optimization keyword research is the process of finding the search terms users type into the App Store and Google Play that match what your app does, then placing those terms in the metadata fields each store indexes. Get the keywords right, and your app surfaces in search results that match user intent. Get them wrong, and your app sits invisible in a category page.

Sometimes called an ASO keyword tool or an app keyword research tool, this kind of workflow turns an app idea into a ranked list of high-intent search terms.

ASO keyword research is not the same as web SEO keyword research. App stores have stricter character limits, fewer ranking signals, and different user intent. Searchers on the App Store are closer to install than searchers on Google: they have a problem and want a solution that works on their phone right now. The keywords you choose decide whether your app is the one they tap.

A keyword generator does not guess. It starts from your app description and expands it in four directions: primary terms that name what your app is, secondary terms that name what it does, long-tail phrases that capture specific intent, and competitor-inspired terms drawn from apps solving the same problem. The habit-tracker example above shows the shape: “adhd habit tracker” is primary, “daily focus timer adhd” is long-tail, and every suggestion carries a difficulty and volume rating so you can tell a winnable term from a wasted one.

The more specific your input, the better the suggestions. “A budgeting app” returns generic head terms every finance app already fights over. “An envelope-budgeting app for couples who share one bank account” returns the long-tail phrases those couples actually search, which is where an app without millions of installs can rank. Feed the generator the sub-category, the audience, and the mechanic, not just the category.

iOS App Store indexes three places: your app name (30 chars), subtitle (30 chars), and the hidden keyword field (100 chars, comma-separated, no spaces). The field is invisible to users but Apple's search algorithm reads it. Repeating words across these three fields wastes characters because Apple deduplicates internally. Single-word density wins; phrases lose.

Google Play indexes your title (50 chars), short description (80 chars), and full description (4,000 chars) in their entirety. There is no hidden field. Google Play rewards natural-language phrases and modest keyword repetition (roughly 4 to 5 mentions of the primary keyword across 4,000 characters). Stuffing gets penalized; phrases beat single words.

The free Keyword Researcher detects which platform you are targeting and adapts: comma-separated single words for iOS, long-tail phrases for Google Play.

The 100-character keyword field is the highest-leverage part of any iOS keyword tool's output, and the easiest to waste. Comma-separate single words with no spaces: “habit,tracker,focus”, not “habit tracker, focus”. Apple builds phrases by combining your field words with each other and with your title, so single words multiply into more matchable phrases than pre-built ones do.

Then recover the characters most apps throw away. Skip plurals: Apple stems automatically, so “tracker” already ranks for “trackers” and listing both burns eight characters for nothing. Never repeat your app name or category in the field, both are already indexed. And use additional localizations as extra keyword space: on the US App Store, Apple also reads the Spanish (Mexico) keyword field, a second 100-character slot most English-only apps leave empty. Filling it with different terms roughly doubles what an English-only app can index in the US.

That extra-localization tactic is the one paid platforms rarely surface and most indie developers never use. The free Keyword Researcher outputs a ready-to-paste comma-separated field, so you can spend the 100 characters on terms you do not already rank for.

Every keyword the tool returns has two ratings: difficulty (easy, medium, hard) and search volume (low, medium, high). The pattern indie developers should target is volume above 20 with difficulty under 60. That window contains keywords with enough searchers to matter and enough headroom for an app without millions of downloads to crack the top 10.

Generic head terms like “game” or “fitness” score hard with high volume. Skip them. Specific long-tail phrases like “habit tracker for adhd” or “language learning for kids” score easy with lower but real volume. Win those first, then expand toward the head as your download velocity grows.

These are two different jobs, and mixing them up wastes money. Keyword research finds and scores the terms worth targeting, the job this free tool does. Keyword tracking watches where your app actually ranks for those terms, day by day, after you ship them. You research once per metadata update; you track continuously.

An indie app rarely needs a paid rank tracker on day one. Research your keywords here, ship them, then validate movement for free: App Store Connect's search-ads keyword suggestions show Apple's own popularity scores, and your App Analytics impressions tell you whether a new term is surfacing. Graduate to a paid ASO keyword tracker like AppTweak or MobileAction once you are managing enough keywords that manual checks stop scaling, usually past a few dozen tracked terms across multiple markets.

Indie devs lose ranking traction to five repeat mistakes. Each costs visibility without being obvious in the data, which is why most show up in keyword research even when the tool itself was decent.

1. Repeating words across title, subtitle, and keyword field. Apple deduplicates internally, so “habit tracker” in your title AND the keyword field wastes 14 of your 160 characters. Use the title for the strongest single word, the subtitle for context, and the field for everything else.
2. Targeting head terms before you have download velocity. Apps with under 10k installs cannot crack top-10 results for “fitness” or “todo”. The first six months belong to long-tail (difficulty under 60, volume above 20), even if it feels small. Volume grows; competitive pressure does not.
3. Translating keywords word-for-word for non-English markets. “Habit tracker” translates literally in 30 languages but matches search intent in maybe 6 of them. The Spanish-language search query is “registro de hábitos”, not “rastreador de hábitos”. Use search-intent translation (the Keyword Translator) instead of Google Translate.
4. Ignoring the screenshot OCR layer. Apple indexes text inside screenshots via OCR. A keyword that appears in your screenshot caption (“Streak counter for ADHD”) joins your indexable set without consuming any of the 160-character metadata budget. Most tools miss this. How Apple OCR indexes screenshot text covers the mechanics.
5. Not re-running keyword research after a category shift. Apple periodically reshuffles category-specific rankings. A keyword set that worked when your app shipped can decay 6 months later. Re-run quarterly and validate with App Store Connect search ads suggestions before paying for a full platform.

Keywords are the input to ranking. Conversion is the output. Once you have your keyword list, three things determine whether searchers actually install:

1. The first three screenshots, the ones the App Store shows in search results before anyone taps in. Build them with the AI Screenshot Builder or follow the Screenshot SEO guide.
2. The subtitle and short description, which carry secondary keyword weight. Use the Subtitle Optimizer to fit them inside the character limits.
3. The full description on Google Play, where natural-language repetition of your primary keywords still moves rankings. The Description Optimizer flags missing keywords and structure issues.