PUBLISHED APP STORE RESEARCH

Bad app reviews.
Better app ideas.Spot the gap.
Build better.

Explore apps with recurring complaints about paywalls, crashes, and usability.
Build the alternative users are already asking for.

Explore all opportunities →

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—Apps Analyzed
—Ranked Opportunities
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ILLUSTRATIVE RESEARCH PREVIEW
DEMO
PDF Scanner Plus
Utilities · Subscription
★1.3/ 5
646,655 ratings
$9.99/mo
Typical Price
#42
in Utilities
TOP COMPLAINT CLUSTERS% OF NEGATIVE REVIEWS
Paywall trapFeels bait-and-switch
41%
Won't exportCan't save or share
29%
Crashes / freezesUnreliable and unstable
18%
ILLUSTRATIVE REVIEW EXCERPTSExample: 646,655 ratings
★★★★★Example

"Charged before I could even scan."

Illustrative scenario
★★★★★Example

"App crashes every time I export."

Illustrative scenario
★★★★★Example

"Paid and still got watermarks."

Illustrative scenario
EXAMPLE RESEARCH SUMMARY

Recurring complaints suggest a problem. Validate demand before building.

OPPORTUNITY SCORE94/100
Illustrative examples · Open the catalog for published research

See the research before you build.

1star.app Explore dashboard showing ranked app opportunities, shortlist filters, and an AI deep dive
Illustrative product view. Open the catalog for the current published research.

Ranked opportunities, with original sources. Free access to the entire catalog and available deep dives.

This isn't one app.
It's 0 of them.

We checked. Systematically.

0stale monetized apps in the dataset

Each entry is algorithmically scored. Available deep dives add sampled complaint themes and AI-assisted ideas. Not every entry has a written deep dive; verify the evidence before investing.

From the published catalog

Find a problem worth solving.

Start with the evidence. Ratings and prices reflect collected observations; revenue figures are estimates, not verified earnings.

Browse the available research.

Explore all opportunities →

All the research. No subscription.

Browse the full catalog, compare opportunities, and read available deep dives for free. A small number of labeled ads support the platform. Ads never influence rankings.

Explore all opportunities →

Yeah but...

Fair questions. Honest answers.

"What do I get for free?"

The entire catalog, filters, and available AI deep dives are free. No subscription or license key. A small number of clearly labeled ads support the platform; ads do not change our rankings.

"How is this different from browsing the App Store myself?"

It's 0 apps already analyzed, scored, and filtered. Current US App Store ratings and update dates, plus clearly dated historical complaint analysis where available. Revenue estimates are withheld until their inputs can be validated. Browse the research for free and verify the original App Store sources before deciding what to build.

"How do I know the data is real?"

Every entry includes a direct App Store link. Click it, read the reviews, check the rating yourself. We're not asking you to trust us - we're giving you the tools to verify in 2 clicks.

"Can I really build a replacement app?"

Use the catalog to find problems to investigate. Check current reviews, competitors, technical requirements, and customer demand before choosing a scope or timeline. A low rating alone does not establish that an app is easy to replace.

From browse to App Store review

From research to a focused prototype.

  1. 1Pick your target

    Open 1star.app. Sort by opportunity score. Read the available research. Click the App Store link and read the 1-star reviews - they wrote your spec for free.

  2. 2Build the MVP

    Validate the complaints with real users. Choose a focused problem, check platform dependencies, and build a prototype.

  3. 3Ship to the App Store

    Test with prospective users, refine the product, and prepare an App Store submission when it is ready.