Storeboard/Guides/How Apple indexes your keywords

How Apple indexes your keywords (and what it ignores)

ASO 16 July 2026 · 6 min read

A lot of App Store optimization advice is recycled Google Play advice. The two stores work differently in one enormous way, and it changes everything you do.

The description myth

Apple does not index your App Store description for search. Not partially. Not with less weight. Not at all.

This is the single most consequential fact in App Store optimization, and it's the one most often gotten wrong — because on Google Play, the description is indexed, and keyword-stuffing it is standard practice. Advice migrates between the two stores and quietly stops being true.

So when you write four thousand words of carefully keyword-dense description, you win exactly zero rankings. That doesn't make the description worthless — it does the selling for people who already found you. But it is a conversion asset, not a discovery one. Write it for humans.

What Apple actually reads

App name (30) · Subtitle (30) · Keyword field (100). Around 160 characters, total, deciding every search query you can appear in.

Each word counts once

Apple builds your searchable index from the name, subtitle and keyword field combined. It then matches queries against that pool — including combinations you never explicitly wrote.

Two consequences follow, and both are routinely ignored:

Repeating a word is pure waste

If your app is called "Somni: Sleep Sounds", then sleep and sounds are already indexed. Adding them to the keyword field again changes nothing — you just spent 12 of your 100 characters buying something you already owned. In practice this mistake costs most apps a quarter of the field.

You don't need to write phrases

Apple combines your indexed words into multi-word queries by itself. You don't need sleep sounds,sleep timer,sleep tracker — you need sleep,sounds,timer,tracker. Writing out phrases duplicates words you already have and burns the field for nothing.

The mechanical rules worth internalising

No spaces after commas. a,b,c not a, b, c. Each space is a character you paid for. Over a full field that's an entire extra keyword.
Don't include your category. It's already associated with your app.
Don't include "app". It's the least differentiating word available to you.
Don't duplicate singular and plural. Apple handles a reasonable amount of stemming; pick one.
Don't use competitor brand names. It's a trademark problem, and it invites rejection.
The keyword field is invisible to shoppers. It doesn't need to read nicely — it needs to be dense.

Where the name and subtitle fit

The name carries the heaviest weighting, which is why so many apps are called "Brand — Keyword Keyword". That works, but it costs you brand clarity, and 30 characters go fast.

The subtitle is the underrated one. It's indexed, it's visible, and it's the only place that has to do both jobs at once: rank and persuade. The best test for a subtitle — does it add words the name doesn't already have, and would a stranger understand what the app does from name + subtitle alone? If it restates the name, it's doing half its job.

Stop guessing at the 100 characters

Storeboard checks your name, subtitle and keywords against each other, flags repeated words, and shows Popularity, Difficulty and Opportunity per country — free, on your Mac.

Download for Mac

The multi-storefront trick

Everything above describes one keyword field. But you get one per localization — and the four English storefronts (US, UK, Australia, Canada) are four separate localizations.

That's four 100-character fields for the same language. You can target the words Americans use in the US field, and the words Britons use in the UK field. Most apps fill in English (US) and leave the rest empty, which is three free ranking opportunities left on the table. It's the highest effort-to-reward ratio move in ASO, and it costs an afternoon.

What to actually do

Write the name and subtitle first. Make sure they share no words.
List every word already indexed by those two.
Fill the keyword field with terms that appear in neither — single words, comma-separated, no spaces.
Check demand and competition per term, per country. Drop what you can't win.
Repeat for every English variant, then every other language you support.
Leave the description to sell. It isn't part of this.

Apple publishes the field limits but not the ranking algorithm. The behaviours above are well-established across the ASO community and consistent with how the store behaves — but nobody outside Apple has the source code, and anyone claiming certainty about weightings is guessing.