Mined from real App Store and Google Play reviews

The best app ideas are hiding in bad reviews.

Grumpi reads thousands of negative App Store and Google Play reviews and turns user frustrations into ranked ideas for mobile apps.

Browse the reports Custom report

2,000+reviews per niche48hcustom reportsNo subscription

“Paywall after onboarding, deleted.”★☆☆☆☆“Four taps to log one habit.”★★☆☆☆“Cancelling my subscription took 20 minutes.”★☆☆☆☆“Love it, but no widget in 2026?”★★★☆☆“Lost two years of data after the update.”★★☆☆☆“Ads every 30 seconds. Unusable.”★☆☆☆☆“I only need the shopping list part.”★★☆☆☆“No way to share it with my partner.”★★★☆☆

“Lost two years of data after the update.”★★☆☆☆“Ads every 30 seconds. Unusable.”★☆☆☆☆“I only need the shopping list part.”★★☆☆☆“No way to share it with my partner.”★★★☆☆“Paywall after onboarding, deleted.”★☆☆☆☆“Four taps to log one habit.”★★☆☆☆“Cancelling my subscription took 20 minutes.”★☆☆☆☆“Love it, but no widget in 2026?”★★★☆☆

The problem

Every ignored complaint is a niche waiting for its app.

Big apps ignore their angriest users. A small team that listens can win them over.

Inside a report

Every idea comes with its evidence.

Score, volume of complaints, apps concerned and verbatim quotes. No guesswork, no vanity metrics.

PricingIdea #01 · Habit trackers

A habit tracker you buy once.

Users quit when a basic tracker locks streaks and history behind a subscription.

Mentions

412

Apps

Switch intent

high

/ 10 · score

“I paid for premium and it still won’t let me edit a past streak.”

“All I want is a checklist. Why a subscription?”

Missing featuresUX frictionPricing painUnbundlingBugs set aside

How it works

01 — Mine

We dig through the reviews.

The latest 1 to 3 star reviews of apps with lots of users and a mediocre rating, across five App Store countries and Google Play.

02 — Extract

Every frustration, quoted.

Each complaint becomes a friction with a verbatim excerpt, then frictions are grouped into problems across apps.

03 — Rank

Only the gems are left.

Problems turn into app ideas a small team can ship in weeks, scored on demand, competition and switching power.

Pricing

Weeks of research, in one report.

Thousands of reviews read and sorted for you. You know what to build, and why users will switch to it. Instant for a niche report, 48 hours for a custom one.

Niche report

$29 one-time

Ranked app ideas with scores
Pain points and verbatim quotes
Apps analyzed and method

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Credits

Your own account and library
Run any keyword, on demand
Early-access pricing

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