App Store Character Limits and What's Actually Indexed for Search

The 160-character search surface

Three fields make up everything Apple indexes for App Store search: the app name (30 characters), the subtitle (30 characters), and the keyword field (100 characters). That's 160 characters total, and it's the entire text surface the search algorithm reads to decide what your app is relevant for.

Every other piece of visible text on your product page exists for conversion, not discovery. Getting this distinction wrong is one of the most common metadata mistakes: writing careful, keyword-rich promotional text or description copy that has zero effect on what you rank for.

What's genuinely not indexed

Promotional text (170 characters) sits at the top of the product page and can be updated at any time without a new binary submission, which makes it useful for timely messaging — a sale, a seasonal push, a new feature callout. It is not indexed for search under any circumstance, so don't spend it on keywords you're hoping to rank for.

The full description (up to 4,000 characters) is similarly not indexed on iOS. This is a real difference from Google Play, where the description does factor into search. An App Store description written purely for keyword coverage, in the style that might work on Android, wastes the opportunity to actually persuade a reader who has already seen your name, subtitle, and screenshots.

What's New release notes are also not indexed. Write them for existing users deciding whether an update is worth installing, not for search visibility.

The screenshot exception

Since June 2025, Apple has been extracting text from screenshot captions via OCR and using it as a ranking signal. This is a real change from older ASO advice that treated screenshots as pure conversion assets with zero connection to search ranking.

The practical implication: caption text overlaid on your screenshots is now doing double duty, same as the subtitle. It should read well to a human deciding whether to install, and it can carry keyword relevance you're not able to fit into the 30-character subtitle limit.

This is a secondary signal, not a new primary field to obsess over. Don't sacrifice screenshot clarity or conversion quality to jam in keywords — a caption that reads as a keyword list rather than a feature callout is a worse trade than accepting a smaller indexing benefit.

Spending the 160 characters well

Because the searchable surface is fixed and small, every character in the name, subtitle, and keyword field should earn its place. Words already in your name don't need to be repeated in the subtitle or keyword field — Apple has already indexed them once, and repetition doesn't add ranking weight, it just wastes space you could use for a new term.

The keyword field specifically rewards precision: no spaces within phrases (commas separate individual words, which are indexed independently), no stop words, and no terms already covered elsewhere in your metadata. A keyword field at 80 of 100 characters used has 20 characters of coverage you're leaving on the table for free.