Does the iOS subtitle affect keyword rankings?

Yes: Apple includes the subtitle in search relevance. That does not mean a subtitle edit guarantees a higher position.

What Apple actually confirms

Apple lists the title, subtitle, keywords and primary category among text-relevance signals. Downloads, ratings, reviews and other user behavior also matter. This confirms that the subtitle can affect matching and ranking, not a fixed weighting or a guaranteed improvement. Promotional text is different: Apple says it does not affect search ranking. Do not treat the two fields as interchangeable. [1]

Write for the searcher and the reader

The subtitle allows up to 30 characters and is visible below the app name. Use it to explain a real benefit in natural language. For a hypothetical reading app, Reading practice for kids is clearer than The best experience ever. These are writing examples, not measured ranking results. Research the audience’s vocabulary in each storefront rather than translating English keywords mechanically. Check the final length in App Store Connect. [2]

Test the change without inventing causality

Record your existing subtitle, release date and target search positions before changing it. Keep other metadata stable where practical; also log advertising, pricing and product changes. After the update is live, compare repeated observations in the same country alongside search impressions, downloads and conversion. A position change alone does not prove the subtitle caused it. App Analytics can include Apple Ads traffic, so account for campaign changes. AsoTheory can track observed positions; it cannot promise which subtitle will win. [1]

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