Find the users you never built for
One deep research prompt that surfaces customer groups you never targeted, proves each one is real with actual reviews and posts, and tells you where to find them.
My baseball alerts app was built for one group: the families of minor league players. Then card collectors found it, tracking the prospects in their binders. Then fantasy managers chasing call-ups before the news broke, a college program following its alumni in the pros, and eventually the players themselves checking their own stat lines. Four groups I never built for are now most of my users. This is the prompt for finding yours on purpose instead of by luck.
Best results: run this in the deepest research mode you have, ChatGPT or Gemini Deep Research, or Claude's extended thinking with web search on. One paste, one run.
Somebody is already using your app for something you didn't intend
WD-40 was invented to stop rust on missile skins. Today the company's site lists more than 2,000 uses for it, and the company didn't write that list. Customers did. It ended up on squeaky hinges and stuck zips and crayon marks because enough people saw the can to find their own reason to buy it.
Once you start looking, the pattern is everywhere, and it's usually worth more than the original product. Minoxidil was a blood pressure drug whose most notable side effect was hair growth, and that side effect became Rogaine. Semaglutide was a type 2 diabetes drug until people noticed what it did to appetite, and most of the world now knows it as Ozempic. In both cases the thing that made it famous was not the thing it was built for, and the people who made it were among the last to work that out.
Your app is the same story at a smaller scale. Someone has already opened it for a reason that never occurred to you. You can't see them because you're looking at your product the way you described it on your App Store page, and they found it by describing it as something else entirely.
That's the whole job, and it happens to be the one thing AI is genuinely good at: restating your product a hundred different ways until one of those descriptions turns out to belong to somebody else.
The prompt
It does three things in one run.
First it strips your product down to what it mechanically does, with none of your industry's words left in it. This part matters more than it looks. "An app for the families of minor league players" leads nowhere, but "tells you the moment a specific person's numbers change, before the people around you know" leads straight to card collectors and fantasy managers. Same app, different sentence.
Then it generates candidates from that stripped-down version. It makes itself list the obvious answers first and then bans them, so it can't hand you "students" and "small business owners" and call it a day.
Then it goes looking for proof that each group actually exists, and deletes the ones it can't prove.
Swap the two [BRACKETS] for your product and paste the whole thing in.
Find customer groups for my product that I never built it for.
My product: [WHAT IT DOES]
Originally built for: [WHO I BUILT IT FOR]
Work in three parts, in one pass. Parts 1 and 2 need no searching at all — do all of that thinking before you open a single link, and print part 1 as the opening section of your report. If your output doesn't start with the four rungs of the ladder, you skipped the step that makes this work.
=== PART 1: THINK (no searching yet) ===
Do not propose any new audiences yet. The only audiences you may name here are the obvious ones in item 2, which exist so we can ban them in part 2.
1. THE LADDER. Restate what my product mechanically does, four times, each one more abstract than the last. Level 1 can use my industry's words. Level 4 must contain zero nouns from my industry - no product category, no market, no jargon a competitor would use. A good level 4 sounds like: "tells you the moment a specific thing you care about changes, before the people around you know." A bad level 4 sounds like: "helps people stay organized" - that's a vague benefit, not a mechanic.
2. THE OBVIOUS LIST. Name the 5 audiences any competitor would name in ten seconds if I asked them who else might use this. Be honest and include the boring ones. This becomes the ban list, so it has to be the real answer, not a strawman.
3. THE COMPLAINT LIST. My product's 5 biggest limitations and likely one-star complaints - what it does badly, what it refuses to do, who it annoys. Include the ones I'd be defensive about.
4. THE WORKAROUND LIST. 5 ways someone could get roughly this outcome today without my product at all - the spreadsheet, the group chat, the alert they set manually, the person they pay, the thing they check every morning. Describe the actual mechanics of each, not the category.
Print all four before continuing. Do not propose a single audience beyond the obvious list.
=== PART 2: GENERATE (still no searching) ===
Now ignore who I built it for. You have explicit permission to reinterpret my product far past my stated market. I care more about being surprised than about being right. Work from level 3 and level 4 of the ladder, never from my product category.
Generate 30 candidates and print all 30 first as a bare numbered list, names only. Then develop the best 10. I want to see the discard pile - the good one is often sitting in it.
Build them with these five lenses, and use every lens at least twice:
- JOB: who else needs the level 4 outcome, for a completely different reason?
- TRIGGER: what exact moment sends someone looking for this today? Who lives inside that moment on repeat?
- WORKAROUND: who is doing one of the part 1 workarounds by hand right now, and hates it?
- CONSTRAINT: who wants this but is blocked by money, skill, time, access or rules - and who has given up on this job entirely because the tools cost too much, need too much skill, or don't exist where they live? Name the blocker precisely.
- ADJACENT ROLE: name the event, object or person my product watches or acts on. Who ELSE is standing around that same thing for their own reason? List every role in the room, not just my customer.
Rules:
- Label every group with a distance band: NEAR (adjacent to my stated market), ONE STEP OUT, or SOUNDS INSANE. At least 4 must be SOUNDS INSANE. Do not self-censor a group for looking impractical - judging that is my job, not yours.
- At least 3 groups must be people who would never think to look at a product in my category at all.
- Banned: the 5 obvious answers from part 1, and any group that is my stated market reworded, resegmented, or handed an adjective. Also banned as group names: students, small business owners, hobbyists, freelancers, content creators, busy professionals, enthusiasts, beginners.
- Demographics are banned as the defining feature. Age, gender, income and location may describe a group but can never be what makes it a group.
- Every group must be nameable as something a real person would put in their own bio, or as a place I could open in a browser. "Parents" fails. "Travel-team parents who run the team group chat" passes.
- For each group, name the sub-group who has this need in the most extreme form. Extreme users post about it, build spreadsheets for it and complain loudly, which is how we find evidence in part 3.
One line each: GROUP - BAND - the lens it came from - the job in their words - what they use instead today - a 0-100 guess at how likely it is this group already exists AND is already looking. That guess is speculation and does not carry into part 3 as evidence.
=== PART 3: VERIFY (now search) ===
Now try to kill all 10 groups and show me the survivors, with proof.
VERIFY IN THIS ORDER: the 3 highest-likelihood groups first for cheap wins, then EVERY group in the SOUNDS INSANE band, then the rest. If you run out of search budget it must never be a SOUNDS INSANE group you skipped - those are the reason I'm running this.
WHERE TO SEARCH:
0. My own data, if I pasted any in above. If I have given you my reviews, support emails, cancellation replies or analytics, mine those FIRST and treat them as the strongest evidence available. Nobody can fabricate my own inbox.
1. Competitor reviews. Highest yield on the open web, because people describe their real use case unprompted.
a. Find apps in my space:
https://itunes.apple.com/search?term=YOUR+SEARCH+WORDS&entity=software&limit=25&country=us
That returns trackId (the app ID) and userRatingCount. Skip anything under roughly 500 ratings, there is no review corpus worth reading.
b. Read their reviews:
https://itunes.apple.com/us/rss/customerreviews/page=1/id=APPID/sortBy=mostRecent/json
page=1 through page=10, 50 reviews each - page 11 returns an error, so stop at 10. Swap /us/ for /gb/, /ca/, /au/ or /in/ to get a completely different set per storefront.
c. Do NOT try to read reviews on apps.apple.com. That page contains star counts and zero review text - the reviews load separately - so if you "read" that page you are inventing the quotes. Use the RSS URL above.
Read for one thing: reviewers describing a use the app clearly was not built for. Those are my groups, already in the wild.
2. Off-label tutorials. Find posts, videos and threads where someone TEACHES other people to use a product like mine for a purpose it was never sold for. Someone bothering to write the tutorial is the single strongest proof that a group already exists.
3. Aggregate demand:
https://suggestqueries.google.com/complete/search?client=firefox&q=YOUR+QUERY
Best shapes: "using [COMPETITOR] for" and "is there an app like [COMPETITOR] but for". Completions only appear when lots of real people type that phrase, so treat each one as a lead worth chasing, not as proof that a group exists.
4. Workaround and technical talk:
https://hn.algolia.com/api/v1/search?tags=comment&query=YOUR+PHRASE
Use unquoted phrases like: I use it for / anyone else use / wish there was one for. Do not wrap them in quotes, that endpoint treats quotes as exact-match and will return nothing. Each hit has an objectID that maps to news.ycombinator.com/item?id=OBJECTID.
5. Reddit, forums, YouTube, Facebook groups, and the industry filter on G2 or Capterra if my product is B2B. Reddit blocks most AI crawlers, so if you cannot actually open the page, do not describe what is on it. Hand me the search string to run myself and mark it NOT VERIFIED.
EVIDENCE RULES, non-negotiable:
- Only sources you actually opened in this session count. Do not recall a community, thread or number from memory.
- Every group needs one VERBATIM sentence written by a real person, 30 words or fewer. Not a paraphrase, not a summary. Copy it exactly, bad grammar and all.
- If you cannot find a real quote AND a real named place, DELETE the group. Do not describe it, soften it, or pad the list to a round number. Three proven groups beat eight plausible ones.
- If you found something but could not open or confirm it, keep it and write NOT VERIFIED beside it. Never quietly promote a guess to a fact.
- Never invent a community. If none exists for a group, write NO COMMUNITY FOUND. That is a real and useful result.
- Do not give me a confidence score on the final list. You rate your most familiar answers highest, which is backwards for this job. Rank by evidence tier instead.
FOR EACH SURVIVING GROUP:
- The group, named the way they would name themselves
- The job and the moment: what they are trying to get done, and the specific situation that sends them looking. Not a demographic.
- What they would have to fire to hire me: the spreadsheet, the app, the alert, the person, the habit
- Buyer vs user: whether the person who would pay and the person who would use it are the same person
- EVIDENCE: the verbatim quote, who wrote it (username or reviewer nickname), the date, the star rating if it is a review, the source type, and the exact URL I can reopen
- EVIDENCE TIER: A = someone is already doing this with a product like mine. B = the group clearly expresses the need, but nobody is visibly using a product like mine for it. C = reasoning only, no artifact found.
- WHERE: the named place they gather (subreddit, Discord, Facebook group, forum, newsletter, hashtag, event, trade publication), roughly how many people are in it, one search string that resurfaces this group from scratch, and concretely how I get in front of 100 of them this week
- COST TO THE CORE: what serving this group would force me to build, support or compromise for the users I already have, and whether that conflicts
- What would have to be true for me to conclude this group is not real
RANK by evidence tier first (A above B above C), then by how cheaply I can reach them. Do not rank by how excited you are about an idea.
Then, for the top 3 only, design a 7-day test that changes nothing about my product:
- the exact headline or post title, written in that group's vocabulary and not mine
- the one specific place to put it
- the number that counts as a real signal, and the number that means no
Finish with one line: which single group you would bet on, and what would prove you wrong.
Don't trust the list until you've opened three links
An AI asked to find communities will invent them. Not occasionally, routinely: believable subreddit names, realistic usernames, quotes that nobody ever wrote. The prompt pushes hard against this by demanding a real quote and a real link for every group, but check it anyway before you act on anything.
Open three links from the results. Each type of source has its own tell.
- App Store review quotes. These aren't in Google's index, so searching an exact quote returns nothing even when the review is completely real. Reopen the RSS link it gave you and search the page for the quote instead. If the nickname and date match, it's real.
- Reddit, forum and YouTube quotes. These are indexed. Paste the sentence into Google inside quotation marks. Zero results means the AI wrote it.
- Communities. Just open the URL. A made-up subreddit 404s or shows "there aren't any communities". A real one shows a member count, which is why the prompt makes it state the size up front, so a mismatch is obvious.
If one link is dead, run the search half again and throw out everything it marked NOT VERIFIED.
What a good answer looks like
The results come back sorted by how far each group sits from the market you're already in. The near ones are the ones you'd have thought of in the shower, and they're mostly there to show the model understood the question. The far-fetched pile is the point, so read that first, before you've decided whether the whole thing was worth running.
Two things are worth checking closely.
The four-line description at the top is load-bearing. Every group below it was generated from the last of those four lines, so if that line came out as a vague benefit like "helps people stay organised" instead of an actual mechanic, everything after it is mush. Make it write those lines again before you let it carry on.
Your worst review is somebody else's headline feature. That's the Rogaine move, and it's why the prompt asks you for your product's biggest complaints and limitations rather than its strengths. The thing you apologise for is sometimes the thing another group is searching for.
Where else to look
The AI does the heavy lifting, but the best evidence is usually already sitting in your own account, and nobody can fabricate it. Paste anything you find into the prompt along with everything else.
- Your 5-star reviews and your support inbox. Anyone describing a use you didn't build is a group, not a one-off.
- Your competitors' 1-star reviews. Complaints from people who were never the target market are the loudest signal there is.
- Your analytics anomalies. A country, device, referrer or time-of-day cluster you can't explain is usually a segment in disguise.
- The words people actually searched. Google Play Console shows the exact terms people typed to find your listing, and Search Console does the same for your website. Apple only reports "App Store Search" as a single lump, so Apple Search Ads is the only way to get the equivalent.
You can also read demand straight off Google's autocomplete in about ten seconds. Open this in a browser:
https://suggestqueries.google.com/complete/search?client=firefox&q=using+[COMPETITOR]+for
It's sharpest on products built for one narrow purpose. using strava for comes back with treadmill, walking and swimming. is there an app like duolingo but for comes back with sign language, the bible and exercise. Every one of those is a real group using something for a purpose it wasn't sold for. On a product that's already general it returns mush, though: using notion for gives you task management, work and school, which tells you nothing. If that's what you're seeing, your product is broad and this particular trick won't help you. Also skip the is there something like X for phrasing, because Google quietly rewrites it into generic "alternative" queries.
How to use it
- Fill in the two [BRACKETS]. [WHAT IT DOES] is the bare mechanics with no marketing ("sends a push when a player's stat line changes", not "keeps fans connected"). [WHO I BUILT IT FOR] is the market you actually had in mind. Everything past that is the AI's job.
- Turn on deep research and paste it once. Add your own reviews, support emails and analytics oddities at the bottom if you have them.
- Read the far-fetched groups first, and check the four-line description before anything else.
- Test before you build. Run the 7-day test it designs for your top group and change nothing about the product until someone outside your stated market puts their hand up. Then take that group over to find your first users and go work the room.
And the cheapest version of all of this, the one WD-40 actually did: ask your users what they use your app for, in public, then read the answers.
I'm building ProveMyApp so founders like you can connect your apps, track their growth with verified metrics, and build alongside other founders instead of doing it alone.
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