App Store Optimization (ASO)

App Store Optimization is how you make your app discoverable when users search the App Store or Google Play. Think of it as SEO for app stores. Most of your organic downloads will come from store search — getting this right is the highest-leverage marketing work you can do.

App name (most impactful factor)

Your app name is the strongest ranking signal on both stores.

Include your primary keyword: “FitTrack - Workout Logger” ranks for “workout logger” while “FitTrack” alone doesn’t
30 characters max on both stores
Put the brand name first, keyword after a dash or colon: “Mealio - Meal Planner”
Don’t keyword-stuff — “FitTrack Workout Fitness Exercise Gym” looks spammy and Apple may reject it

The name is the single most important ASO element. Spend time getting it right.

The subtitle appears directly below your app name in search results. 30 characters max.

Use it as a secondary keyword opportunity — don’t repeat words from your name.

Name: “FitTrack - Workout Logger”
Subtitle: “Gym Plans & Progress Photos”

This gives you coverage for “workout logger,” “gym plans,” and “progress photos” across just two fields.

Keywords (App Store only)

The App Store has a dedicated 100-character keyword field (comma-separated, not visible to users). Google Play doesn’t have this — it indexes your description instead.

Tips for the App Store keyword field:

Don’t repeat words already in your app name or subtitle — Apple indexes those automatically
Use singular forms — Apple matches plurals from singulars
Don’t include spaces after commas (wastes characters)
Include synonyms and related terms users might search for
Include common misspellings of competitor names if relevant
Don’t include your own app name or the word “app”

Example for a meal planning app:

Name: “Mealio - Meal Planner” / Subtitle: “Recipes & Grocery Lists”

Keyword field: diet,nutrition,food,cooking,weekly,prep,healthy,eating,calories,tracker,budget,family,dinner,lunch,breakfast

Notice: no “meal,” “planner,” “recipe,” or “grocery” — those are already in the name and subtitle.

Description

App Store (iOS)
Google Play

Apple does not index the long description for search rankings. Write it for humans, not keywords.

Lead with your strongest value proposition in the first sentence
Use short paragraphs — walls of text get skipped
Bullet-point your key features (3–5 is enough)
End with a call to action (“Download FitTrack and start your first workout today”)
The first 3 lines are visible before the “more” button — make them count

Screenshots and icon

Your visual assets drive conversion rate — the percentage of people who view your listing and actually download.

First 2–3 screenshots are visible without scrolling. Make them your best.
Use text overlays that describe benefits, not features
See App Store Screenshots for the full guide on sizes, tools, and strategies
Your icon should be simple, bold, and recognizable at small sizes
See App Icon for design guidance

Ratings and reviews

Apps with more (and higher) ratings rank better and convert better. A jump from 3.5 to 4.5 stars can double your conversion rate.

How to get more ratings:

Ask Primio to add a native rating prompt:

“Add an in-app review prompt that appears after the user has completed 5 sessions. Use the native in-app review dialog (StoreKit for iOS, Google Play In-App Review API for Android). Only show it once.”

Timing matters. Ask for a rating after a positive moment — when the user completes a task, achieves a goal, or has a success. Never ask during onboarding, after an error, or when the user is clearly frustrated.

Respond to reviews. Both stores let you reply publicly. Responding shows potential users that the developer is active and cares. Address negative reviews constructively — fix reported issues, then reply with what you fixed. Users often update their rating after a developer responds.

Don’t ask for ratings too early, too often, or at annoying moments. This leads to 1-star reviews from frustrated users.

Regular updates

Both stores favor apps that update regularly.

Each update is a chance to revise your store listing (screenshots, description, keywords)
Update at least monthly if possible
Meaningful updates (bug fixes, new features) signal an active, maintained app
Include clear, user-friendly release notes describing what changed
Increment your version number with each update

Regular updates also reset your “editorial consideration” — Apple’s editorial team is more likely to feature recently updated apps.

Category selection

Choose your category carefully:

Pick the category that most accurately describes your app
Check how competitive the category is — a fitness app might rank higher in “Health & Fitness” than in a more competitive general category
You can set a primary and secondary category on both stores
Research what category your competitors use

Localization

If your app works in multiple languages, localizing your store listing can dramatically increase downloads in non-English markets.

Translate your app name, subtitle, keywords, description, and screenshots
Start with your top 2–3 target markets by download volume
Even if the app itself is English-only, a localized store listing helps discovery
Use local keywords — direct translations often aren’t what people actually search for

ASO research tools

AppTweak (apptweak.com) — Keyword research, competitor tracking, ASO score (free tier available)
Sensor Tower (sensortower.com) — Market intelligence, keyword rankings, download estimates
App Radar (appradar.com) — ASO optimization and keyword tracking (free tier available)
Primio’s App Discovery — Use App Discovery to research competitors, see what’s ranking in your category, and identify keyword opportunities from top apps’ names and descriptions

Writing effective descriptions

A good description converts browsers into downloaders. A bad description — even for a great app — loses users who never scroll past the first line.

Structure that works

Hook (first 1-2 lines) — Lead with the primary benefit, not a feature list. “Plan your meals in 30 seconds and never wonder what’s for dinner” beats “Mealio is a meal planning application.”
Key features (3-5 bullets) — Each bullet starts with a benefit, then explains the feature. “Save hours each week — auto-generate grocery lists from your meal plan” is better than “Grocery list generation.”
Social proof (if available) — User count, ratings, press mentions. Skip this for new apps.
Call to action — “Download [AppName] and [achieve the benefit] today.”

Common mistakes

Walls of text — Use short paragraphs and bullet points. Nobody reads a 4-paragraph block.
Feature lists without benefits — “Push notifications” means nothing. “Never miss a workout — smart reminders keep you on track” sells.
Mentioning unbuilt features — “Coming soon” in a description is a red flag. Only describe what the app does now.
Using competitor names — Both stores prohibit mentioning other apps or trademarks in your listing. “Better than [CompetitorApp]” will get flagged.
Keyword stuffing — “Best fitness app workout app gym app exercise app” reads like spam and Google actively penalizes it.

Platform differences

App Store (iOS): Apple does not use the long description for search rankings. Write entirely for humans — clarity and persuasion matter more than keyword density. The first 3 lines show before the “more” button, so front-load your strongest pitch.
Google Play: Google indexes the full description for search. Use your target keywords naturally throughout, but prioritize readability. Aim to use important keywords 3-5 times across the full text without sounding forced.

ASO checklist

Use this when preparing or updating your store listing:

App name includes primary keyword (under 30 characters)
Subtitle (iOS) or short description (Android) adds secondary keywords
Keyword field (iOS) uses all 100 characters without repeating name/subtitle words
Description is optimized (human-focused for iOS, keyword-rich for Google Play)
Screenshots have benefit-focused text overlays
First 2–3 screenshots showcase the strongest value
App icon is distinctive and readable at small sizes
In-app rating prompt is implemented at an appropriate moment
Category is chosen strategically

Next steps

App Store Screenshots

Create compelling screenshots with the right sizes and tools.

Marketing Your App

Drive downloads with organic content, influencers, and launch strategies.