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Niches
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Glossary
The words of the app business, in plain English.
Finding a niche
App niche
An app niche is one job people go to the app stores for — scan a receipt, identify a plant, track a habit — together with the apps that already answer it.
Neglected app
A neglected app is one whose developer has not shipped an update in nine months or more — often a sign its users are waiting for a better alternative.
Rankability (keyword difficulty)
Rankability is how realistic it is for a new app to reach the top of a store search — the gap between how much a phrase is searched and how strong its current leaders are.
Ratings velocity
Ratings velocity is how fast an app gains new ratings — a proxy for how many people are installing it now, since neither store publishes downloads.
Top ten (niche leaders)
A niche's top ten are the first ten apps a store shows for its search phrase — the competition a new app has to beat to be seen.
App stores and ASO
App Store keyword field
The keyword field is a hidden, 100-character list of search words each App Store app can set; users never see it, but search reads it.
App subtitle
The subtitle is the 30-character line under an app's name on the App Store, shown in search results and read by search.
ASO (app store optimization)
ASO is the work of making an app rank higher and convert better in App Store and Google Play search: its name, subtitle, keywords, screenshots and ratings.
Custom product page
A custom product page is an alternative version of an App Store listing — its own screenshots, previews and promotional text — with its own link, for a specific ad or audience.
Install band
An install band is the download range Google Play prints on each listing — 10,000+, 1,000,000+ — a floor on how many times the app was installed.
Product page optimization (A/B testing)
Product page optimization is Apple's built-in A/B test for store pages: it shows different icons, screenshots or previews to different visitors and measures which converts better.
Search suggestions (autocomplete)
Search suggestions are the phrases the App Store and Google Play offer as you type — a public trace of what people actually search, roughly in order of how often.
Pricing and revenue
App store commission (15% or 30%)
Both stores take 30% of digital sales as standard and 15% for small developers: Apple's Small Business Program covers developers earning up to $1M a year, and Google Play charges 15% on each developer's first $1M a year.
Free trial
A free trial lets a user try a paid plan for a few days before the first charge, and converts to a paid subscription unless cancelled.
Freemium
A freemium app is free to download and use, with a paid upgrade for more features, more usage or no ads.
Hard paywall vs soft paywall
A hard paywall blocks the app until the user pays or starts a trial; a soft paywall lets them use part of it free and asks later.
In-app purchase (IAP)
An in-app purchase is anything bought inside an app through the store — a subscription, a one-time unlock, or a pack of credits.
Lifetime purchase
A lifetime purchase is a one-time payment that unlocks an app's paid features for good, sold alongside or instead of a subscription.
LTV (lifetime value)
LTV is the total revenue an average paying user brings over the whole time they stay, after the store's commission.
Paywall
A paywall is the screen that asks a user to pay — to start a subscription or unlock features — before going further.
Metrics and growth
ARPPU (average revenue per paying user)
ARPPU is an app's revenue in a period divided by only the users who paid in that period.
ARPU (average revenue per user)
ARPU is an app's revenue in a period divided by all its active users in that period — paying or not.
CAC (customer acquisition cost)
CAC is the total cost of winning one paying customer — not one install, but one person who pays.
Churn
Churn is the share of paying subscribers who cancel in a period — per month for monthly plans, per year for yearly ones.
Conversion rate
In apps, conversion rate usually means the share of downloads that become paying users — typically a few percent for apps that sell something.
CPI (cost per install)
CPI is what an advertiser pays, on average, for one install from a paid campaign.
DAU/MAU (stickiness)
DAU/MAU is daily active users divided by monthly active users — the share of a month's users who use the app on a typical day.
MRR and ARR (recurring revenue)
MRR is monthly recurring revenue — what active subscriptions bring in each month; ARR is the same figure for a year, usually MRR × 12.
Organic installs
Organic installs are downloads that came without paid advertising — from store search, browsing, word of mouth and links.
Retention rate (D1, D7, D30)
Retention rate is the share of users who come back to an app a given number of days after installing it — on day 1, day 7 and day 30 are the usual checkpoints.
ROAS (return on ad spend)
ROAS is the revenue a campaign earned divided by what it cost — 150% means every dollar spent brought back $1.50.
Trial conversion rate
Trial conversion rate is the share of free trials that turn into a first paid period.
Building an app
AI wrapper
An AI wrapper is an app whose main value is a single call to someone else's AI model, with an interface around it.
Micro SaaS
Micro SaaS is a small software-as-a-service business, usually run by one person or a tiny team, that serves a narrow audience for a subscription.
MVP (minimum viable product)
An MVP is the smallest version of a product that does its core job well enough for real users to use — and, ideally, pay for.
Product-market fit
Product-market fit is the point where a product satisfies a market well enough that people keep using it, pay for it and tell others without being pushed.
Vibe coding
Vibe coding is building software by describing what you want to an AI coding tool and accepting what it writes, with little reading of the code itself.