Reference

App Store metadata, field by field

Which fields Apple searches, which it only shows, and what each costs you in characters.

The App Store searches three of your fields and shows the rest. Knowing which is which is most of App Store ASO, because every character in an indexed field is scarce and every character in the others is free.

The fields it searches

Sixty visible characters and a hundred hidden ones. That is the whole indexed surface, and it is the reason App Store metadata is an allocation problem rather than a writing problem.

The fields it does not

This is the single most common mistake in App Store listings: a carefully keyword-written description, which Apple does not read. Write it for the person deciding whether to install, because that is the only job it has — and conversion feeds back into ranking anyway.

The rules that decide how far your characters go

A word counts once

Apple builds one index from your name, subtitle and keyword field together. A word in all three ranks exactly as well as a word in one, and has cost you three times the characters. Deduplicate across fields before you do anything else — it is usually the largest single gain available in an App Store listing.

Apple builds the phrases for you

You do not need to write phrases. Words are combined across fields, so sleep, sounds and timer can rank for "sleep sounds", "sleep timer" and "sounds timer" without any of those phrases appearing anywhere. This is why the keyword field holds single words separated by commas, never phrases: a phrase spends characters on a space and matches nothing the two words did not already match.

Stopwords are dropped

Words like a, the, for, and, with, my, your are ignored by the index. So are app, free, iphone, ipad and download — every listing contains them, so they distinguish nothing. Each one you write into the keyword field is a character bought and thrown away.

Commas, not spaces

In the keyword field, separate with commas and no space after them. A space is a character, and you have a hundred.

Plurals and casing

Apple handles case for you — do not write both. Plurals are less reliable: if a plural form is what people actually type and it is worth a character or two, it can be worth including. Check which form the store's own autocomplete offers before spending on it.

How to allocate the three fields

Rank your keywords by what they are worth to you — demand you could realistically win — then place them by weight:

1. Name (30). Your brand plus your single strongest term. Weighted highest, and the only field a person reads in a result list. If the name is already category words rather than a brand, you have more room here than you think — but dropping a name people search for has a cost that no ranking makes back.
2. Subtitle (30). The next strongest terms, in a line that reads as a sentence to a human. It is shown, so it has to work as copy.
3. Keyword field (100). Everything else, as single words, no duplicates of anything above, no stopwords, comma-separated. Nobody sees this, so it does not need to read well — it needs to be complete.

A worked example

A sleep sounds app, with room already spent badly:

Name:      Deep Sleep · Sounds          (21/30)
Subtitle:  Relax and drift off          (17/30)
Keywords:  sleep,sounds,relax,calm,night,noise,rest,quiet,bedtime   (62/100)

Three problems. sleep and sounds appear in the name and again in the keyword field, so eleven characters are buying nothing. Relax and drift off spends a whole indexed field on one keyword plus two stopwords. And 38 characters of the keyword field are simply unused.

Name:      Deep Sleep: Sounds & Timer   (30/30)
Subtitle:  White noise & rain to sleep   (29/30)
Keywords:  brown,hypnosis,meditation,ocean,fan,baby,nap,insomnia,ambient,drift   (99/100)

Nothing is repeated between the three. The visible fields carry the terms worth showing a person; the hidden field carries the rest at full width. Same app, same release, roughly twice the indexed surface.

Which terms belong in which slot is a question about their value, which is what keyword research is for. The equivalent rules on the other store are in Google Play metadata — they are genuinely different, and a listing copied between the two is wrong on one of them.