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.

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.

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.

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, which 90% of viewers see before scrolling. 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.