Mobile apps are structurally different from SaaS or marketplaces. The buyer is usually an individual consumer, the price point is low, and the dominant failure mode is acquisition: most apps die in the App Store rankings before anyone finds them.
This is a playbook for testing a mobile app idea against the four dimensions that matter most: category economics, retention realism, acquisition channel, and the App Store math.
Dimension 1: Category economics have to be possible
Consumer apps live in a few economic models:
- **Freemium plus subscription.** $4.99 to $9.99 a month is the standard band. Conversion from free to paid is usually 2% to 5%, sometimes lower for utility apps and higher for entertainment. - **One-time purchase.** $1.99 to $9.99 typically. Common for utility and games. Requires either viral acquisition or sustained App Store rank. - **Ad-supported.** Requires very large free user base (hundreds of thousands of daily active users at minimum) to clear meaningful revenue.
The test: pick the model and run the math. For freemium subscription at $5.99 with 3% conversion, you need 100,000 active users to clear roughly $15,000 monthly recurring revenue after platform cuts. Can your category realistically support that?
Dimension 2: Retention has to be possible structurally
Most apps lose 70% of users in week one and 90% by week four. Apps that survive have retention curves that flatten, not curves that approach zero.
The test: identify which structural retention driver applies. The five common ones:
- **Daily habit.** Health and fitness, journaling, productivity. - **Network effects.** Social, dating, messaging. - **Content treadmill.** Reading, entertainment, learning. - **Streak mechanics.** Language learning (Duolingo), habit tracking. - **External trigger.** Banking, e-commerce, ride-sharing.
If your app does not naturally fit one of these patterns, retention will struggle. The fix is usually to design one in before building.
Dimension 3: Acquisition channel has to be specific and testable
Mobile apps acquire from a small number of channels:
- **App Store SEO.** Ranking for category and feature keywords. - **Paid acquisition.** Facebook, TikTok, Google ads. - **Organic referral.** Built-in invite mechanics, social sharing. - **Content/SEO.** Web content drives App Store downloads via badges or links. - **PR/launch.** Single moments of attention from coverage or feature placement.
The test: name the specific channel and the specific CAC band you expect. "We will market it" is not a channel. "We will rank for 'habit tracker for indie hackers' in the App Store, where the top three results today get roughly 80% of downloads" is a channel.
For paid acquisition, the CAC band has to clear the LTV math. At $5.99 a month subscription with 3% conversion and 6-month average tenure, blended LTV is around $1.50 per install. A paid CAC over $1.50 burns money. That math determines whether paid acquisition is the right channel.
Dimension 4: The App Store math has to work
The App Store is a search and ranking system. Apps that do not rank do not get installs. Apps that rank top three in a category get most of the installs in that category.
The test: identify the specific keywords you will target and look at the top three apps currently ranking. If they are all owned by well-funded competitors with huge install bases, the rank is unreachable from a cold start. If the top three include weak, dated, or under-optimized apps, the rank is reachable and worth pursuing.
A worked example: a habit-tracking app for indie hackers
The idea: a habit-tracking app focused on indie hackers and AI builders, with public streak pages and integration with build-in-public posting on X.
- **Economics:** freemium subscription at $7.99 a month. Target 50,000 active users at 4% paid conversion = $16K MRR. Audience is reachable through indie-hacker channels (X, r/IndieHackers, Indie Hackers product page). - **Retention:** streak mechanics plus public streak page (external accountability). Both retention drivers compound. Realistic to see 30% week-four retention if the streak page resonates. - **Acquisition channel:** content + App Store SEO. Rank for "habit tracker for indie hackers" and adjacent terms. Build-in-public posts as ongoing organic channel. Paid acquisition skipped initially because LTV math does not clear typical CAC. - **App Store math:** the top three for "habit tracker" are well-defended brands. The top three for "habit tracker for indie hackers" do not exist as a tight category, which is an opening. Niche rank is reachable; broad category rank is not.
All four dimensions clear. The idea is worth building, with the explicit understanding that the early growth is organic and slow.
How Verdikt fits this playbook
The free Verdikt tests the same four dimensions for mobile apps and returns a Verdikt Score plus the top three named risks. The Single Report ships the full memo, including App Store keyword research, retention-pattern analysis grounded in category benchmarks, and acquisition-channel math.
The playbook above is the manual version. Verdikt compresses it.
A research letter for AI builders.
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