What is App Store Optimization?

App Store Optimization is the work of getting more people to find your app in the App Store and then download it. It has two halves that depend on each other:

• Visibility: showing up, and showing up high, when people search for something your app does.
• Conversion: turning the people who see your app into people who open its page and install it.

Most App Store downloads start with a search, so for a small team ASO is often the cheapest growth channel there is. It costs no ad budget, and every improvement keeps paying off for as long as the app is listed. The trade-off is that results are slow to measure and Apple explains very little about how search works, so it rewards patience and careful testing more than tricks.

On iOS, only a handful of fields decide which searches your app can appear for. Everything else on your product page helps people decide to download, but doesn’t make you findable.

• App name (30 characters). The strongest signal. Words here count for the most.
• Subtitle (30 characters). Shown under the name in search results, and indexed.
• Keyword field (100 bytes). Hidden from users and only visible to you in App Store Connect. Note it’s bytes, not characters, so letters with accents and non-Latin scripts use more than one each.
• In-app purchase display names. Promoted in-app purchases can appear in search, and their names are indexed.
• Developer name. People can find you by searching for your company name.

The description is not used for search on iOS, as far as anyone outside Apple can tell. Promotional text isn’t either. Both still matter, because people read them before downloading.

Apple combines words across the name, subtitle and keyword field. If your name contains “budget” and your keyword field contains “planner”, your app can rank for “budget planner” without that phrase appearing anywhere as written. That’s why you don’t need to repeat words: a word only has to appear once across the three fields.

The keyword field is 100 bytes of pure search value, so every byte should earn its place.

• Separate keywords with commas and no spaces: budget,expense,tracker,savings. Spaces waste bytes.
• Use single words rather than phrases where you can. Apple combines them into phrases for you.
• Don’t repeat words that are already in your name or subtitle. They’re indexed already.
• Skip plurals in most cases. Search generally matches common singular and plural forms.
• Skip filler such as “app”, “the”, “and” or “free”. They rarely help you rank for anything.
• Don’t use competitors’ names or trademarks. It breaks the App Review Guidelines and can get an update rejected.

Pick words people actually type, which describe your app honestly. An app that ranks for a search but doesn’t match what the person wanted gets skipped, and Apple appears to notice when people search, see your app and don’t download it.

Each language you add in App Store Connect has its own name, subtitle and keyword field. Some countries’ search reads more than one language. For example, US search is widely observed to also read the Spanish (Mexico) listing, not just English (U.S.).

Apple doesn’t document which languages each country reads, so treat this as well-tested community knowledge rather than a rule. The practical effect is real, though: filling in those extra languages can give you twice the keyword space for the same country. Use it for different words, not repeats, since a word counted once already gains nothing the second time.

Three questions decide whether a search term is worth a place in your metadata:

• Popularity: how often people search it. Apple shares a 5–100 popularity score only inside Apple Search Ads; tools estimate it in other ways, for example from how early a term appears in App Store autocomplete.
• Difficulty: how hard it is to reach the top results. Search terms dominated by apps with hundreds of thousands of ratings are hard for a new app to break into.
• Relevance: whether someone searching it would be happy to find your app. A popular, easy term is worthless if the people searching it want something else.

New and small apps usually do best with specific, longer searches (“habit tracker for adhd” rather than “habit”) where the competition is lighter. As your app gathers ratings and downloads, broader terms become reachable. Ranking in the top few results matters far more than ranking at all: most people tap one of the first few apps they see.

App Store Connect’s Analytics shows three numbers that together tell you where to work:

• Impressions: how many times people saw your app in search results, on the Today and Apps tabs, or elsewhere in the store.
• Product page views: how many opened your page.
• Downloads: how many installed.

Each step points to a different lever:

• Few impressions? It’s a visibility problem: keywords, name, subtitle, extra languages.
• Plenty of impressions, few page views? People see you in search results but don’t tap. Look at your icon, name, subtitle, rating and the first screenshots, since that’s all they see there.
• Plenty of page views, few downloads? The product page isn’t convincing. Look at your screenshots, preview video, ratings, recent reviews and the first lines of the description.

Rates vary a lot by category, so compare yourself with the benchmarks App Store Connect shows for apps like yours rather than with a single number from a blog post.

Ranking gets you seen. These decide whether you get chosen.

• Icon. It’s tiny in search results. One bold shape and strong contrast work better than detail or text. It should stand out from the icons around it in your category.
• The first three screenshots. In search results on iPhone, people usually see the first few screenshots before tapping anything. Make each one show a clear benefit with a short caption, readable at a glance. Put your best one first.
• Ratings. The star average and count sit right next to your name. A low or tiny count makes people hesitate.
• Preview video. It autoplays muted, so the first few seconds need to show the app working, not a logo animation.

Apple gives you two built-in tools to improve conversion with real data. Product page optimization tests up to three alternative icons, screenshot sets or preview videos against your current page on a share of real visitors. Custom product pages let you make separate versions of your page, each with its own screenshots and link, for specific audiences or ad campaigns. Custom pages can also be tied to keywords in Apple Search Ads.

Ask for ratings with Apple’s built-in prompt (SKStoreReviewController), which iOS shows at most a few times a year per user. Timing matters more than anything else: ask right after a moment of success, such as finishing a task or reaching a goal, never on first launch or after an error.

Reply to reviews in App Store Connect, especially the critical ones. A calm reply that says what you fixed shows future visitors that someone cares, and people who see their problem solved sometimes update their rating. When you ship a big improvement, you can also reset your summary rating with a new version, but you lose the old count with it, so it’s rarely worth it unless the old average is dragging you down.

Name, subtitle and keyword field changes only go live with a new app version, so ASO and your release schedule are tied together. Regular updates keep the listing fresh, give you a reason to tweak metadata, and give returning visitors something to read in What’s New. Write it for people: what changed and why it helps them, not “bug fixes and improvements”.

Promotional text (170 characters, above the description) can be changed at any time without a new version. It isn’t indexed for search, but it’s ideal for timely messages: a sale, a seasonal feature, a new integration.

In-app events appear on your product page and can show up in search results and on the Today tab. A real event, such as a challenge, a season or a major feature launch, gives you another way to be seen and to bring back people who already have the app.

ASO is a loop: change something, wait, measure, keep or revert. A few rules make the measuring honest:

• Change one thing at a time where you can. If you change the name, screenshots and icon in one release, you won’t know which one moved the numbers.
• Give it two to four weeks. Rankings and conversion settle slowly, and day-to-day noise is large for small apps.
• Compare like with like. Holidays, features by Apple, press coverage and ad spend all move the numbers. Note them so you don’t credit or blame the wrong change.
• Track the searches you care about every day, so you can see a keyword climb or drop right after a release.

Most apps need two or three rounds before the listing really settles. After that, a small check-in each month keeps it there.

• Spending name and subtitle space on a brand nobody searches for yet, instead of the words that describe what the app does.
• Repeating the same words in the name, subtitle and keyword field.
• Spaces after commas, plurals and filler words in the keyword field.
• Chasing the most popular terms in the category with a brand-new app.
• Screenshots that show settings screens or walls of text instead of the result people get.
• Never adding the extra languages that count toward your main country.
• Changing everything at once, then guessing which part worked.
• Asking for a rating on first launch.