Free vs Paid Keyword Research Tools for ASO: What $0 Actually Buys You

Do you need to pay for a keyword research tool to do ASO? For most indie developers, not at first. A free stack — App Store and Google Play autocomplete, the search popularity data inside Apple Ads, and the free tiers that several ASO vendors give away — covers the two jobs that matter early: finding candidate keywords and getting a rough read on demand. What paid tools sell is everything after that: historical volume, difficulty scoring at scale, competitor keyword intelligence, and rank tracking you don't have to run by hand. The honest answer is that free gets you to a competent first metadata pass, and paid gets you to iteration speed. Which one you need depends on how many apps you run and what your time is worth.

What keyword research actually consists of

Strip the vendor language away and keyword research is four tasks. You generate candidates (what could people be typing?). You estimate demand (are they actually typing it?). You judge difficulty (can your app realistically rank for it?). And you track results (did the change work?). Every tool, free or paid, is some bundle of those four.

That framing matters because free and paid tools don't split evenly across it. Free tools are surprisingly good at the first two tasks and nearly useless at the last two. Paid tools earn their subscription almost entirely on difficulty and tracking.

The raw material is the same for everyone. On iOS, Apple indexes your app name, subtitle, and the 100-character keyword field — the fields Apple itself documents on its product page guidelines and discoverability overview. On Android, Google Play indexes your title, short description, and long description, with limits of 30, 80, and 4,000 characters laid out in Google's own listing documentation. No tool changes what gets indexed. Tools only change how well you fill those fields.

The free stack, honestly

Autocomplete is the most underrated tool in ASO

Type a seed word into App Store search and read the suggestions. That's it — and it's better data than it looks like, because autocomplete is drawn from what users actually search, ranked roughly by popularity. It costs nothing, it's always current, and it works in every storefront and language. Its limits are just as plain: you get no numbers, no history, and harvesting suggestions at any scale by hand is slow.

Apple Ads search popularity: free demand data with a catch

If you have an Apple Ads account — the account is free; you only pay when you run campaigns — the keyword planning interface shows a relative search popularity indicator for any keyword you look up. Apple's own keyword best-practices documentation describes popularity as the signal to weigh when choosing keywords. Because the data comes from Apple rather than from a third party's estimate, this is the closest thing to ground truth a free tool offers.

The catch: it's a coarse relative scale, not a search count. Practitioners have documented cases where the score behaves oddly — RespectASO's analysis argues the popularity score can mislead on low- and mid-volume terms, which is exactly where indie apps live. Treat it as a filter for obvious duds, not a ranking oracle.

Vendor free tiers and trials

Most paid ASO suites give something away — it's how they fill their sales funnel, and there's no shame in drinking from it. ASOMobile, for example, publishes a set of free tools covering keyword suggestions, autocomplete harvesting, and metadata checks without a paid plan. Others offer time-limited trials of the full product, which are long enough to run one serious metadata revision if you prepare your seed list before starting the clock. We keep a running, price-verified list in our free ASO tools guide, including which "free" offers are real tiers and which are trials in a free hat.

What paid tools actually add

Paid keyword tools are not selling secret data. They're selling four kinds of leverage on the same public stores.

Volume estimates with history. Instead of Apple's coarse popularity bar, paid tools model search volume and show you how it moved over months. For seasonal categories, history is the difference between targeting a keyword and targeting last January's keyword.

Difficulty scoring at scale. Judging whether you can rank for a term means checking who currently ranks and how strong they are — doable by hand for five keywords, not for five hundred. Difficulty scores are estimates and vendors compute them differently, but they turn an afternoon of squinting into a sortable column.

Competitor keyword intelligence. The single feature hardest to replicate for free: paid tools show which keywords a competitor ranks for and roughly which drive their downloads. SplitMetrics' guide to keyword expansion shows how much of professional keyword work starts from competitor lists rather than from imagination. The free equivalent — reading a competitor's visible metadata and guessing — misses their long tail entirely.

Rank tracking. Once metadata ships, you need to know what moved. Manual checking is noisy (results are personalized and vary by storefront) and doesn't scale past a handful of terms. Trackers check daily, from clean profiles, across countries.

Where does that leave price? Deliberately unquoted here — vendor pricing changes often enough that any number in this paragraph would eventually be wrong. When we last verified plans on vendor pricing pages in August, several serious tools had entry plans under $100 a month; the details are in our ASO tools under $100 guide. Check the vendor's own pricing page before believing anyone's screenshot, including ours.

The honest scorecard

Where free wins: candidate generation (autocomplete is excellent), first-party demand signal (Apple's own popularity data beats a third-party estimate for reliability), and cost — which is not a small thing when your app earns $40 a month.

Where paid wins: everything longitudinal. History, tracking, difficulty at scale, and competitor long-tail extraction. If your ASO practice is "revise metadata once, then check back next quarter," paid tools are mostly wasted on you. If it's "iterate monthly and measure," the free stack becomes the bottleneck fast.

The switching trigger is time, not features. When you catch yourself spending hours a month hand-harvesting autocomplete into a spreadsheet and manually checking ranks across two storefronts, you've found your budget line — you're already paying, just in hours.

(For what it's worth, this is the workflow gap we started Kintsu around — it's in private beta, built for indie developers. But the free stack above requires no tool of ours or anyone else's.)

FAQ

Can I do effective ASO with only free tools? Yes, for a first pass. Autocomplete for candidates, Apple Ads popularity for demand filtering, and your own eyes on competitor metadata will produce a defensible name, subtitle, and keyword field. What you can't do well for free is measure and iterate — expect to feel that limit within a couple of release cycles.

Is Apple Ads search popularity accurate? It's authoritative but coarse. It comes from Apple, which makes it more trustworthy than third-party estimates, but it's a relative indicator, and documented critiques show it can flatten meaningful differences between low-volume terms. Use it to rule keywords out, not to fine-rank them.

When should an indie developer start paying for a keyword tool? When manual research becomes a recurring monthly cost in hours, or when competitor keyword intelligence would change your decisions — typically around the point you're actively iterating on metadata for one growing app or managing several. Until then, the free stack plus discipline covers it.