App Store Optimization Basics: How a New App Gets Found on the App Store and Google Play

App Store Optimization covers two jobs. The first is discovery: appearing in store search for the words people type when they need what your app does. The second is conversion: persuading the person who lands on your product page to install. Most ASO advice mixes the two, which is why teams end up rewriting screenshots when the real problem is that the app never shows up for the right searches.

Search is the main door. Apple's advertising team states that 70% of App Store visitors use search to discover apps and that almost 65% of downloads happen directly after a search, based on worldwide App Store data from 2022. Apple also reports that over 850 million people visit the App Store every week. A new app has no brand searches yet, so the words in its metadata are close to the only thing that can put it in front of those visitors.

Apple's search guidance names two groups of signals: text relevance, meaning matches in the app's title, subtitle, keywords and primary category, and user behaviour, including downloads, ratings and reviews. Your primary category and optional secondary category are indexed, so the category is a ranking choice as well as a browsing one. Choosing an irrelevant category is grounds for rejection.

The fields have hard limits. The app name and the subtitle can each be up to 30 characters. The keyword field, which users never see, is limited to 100 characters, with terms separated by commas and no spaces. Promotional text, up to 170 characters, can be changed at any time without a new app version, but Apple states that it does not affect search ranking, so it should carry news and offers rather than keywords.

Google Play has no hidden keyword field. Its help centre says apps are ranked using a combination of ratings, reviews, downloads and other factors, and that search also considers the overall experience of the app based on user behaviour and feedback. The words come from the listing itself: a title of 30 characters or less, a short description of 80 characters or less, and a full description of up to 4,000 characters.

That makes the description a ranking asset on Google Play in a way it is not on the App Store. Google asks for everyday language rather than keyword lists, warns against subtle misspellings of general terms, and recommends keeping the most important text in the top half of the description so it is visible without scrolling. It also asks for unique alt text on each screenshot.

Many ASO tactics copied from older guides now break store policy. Google's store listing best practices are explicit, and Apple's guidance overlaps on most points. Treat these as hard constraints when writing the first draft, not as edits after a rejection.

On the App Store you can show up to 10 screenshots and up to three app previews of up to 30 seconds each. Apple notes that when no preview is available, the first one to three screenshots appear directly in search results, depending on orientation. Those first frames therefore work like an ad in the results list: they should show the core task the app performs, not a logo or a welcome screen. Previews autoplay muted, so the first seconds need to make sense without sound.

Apple says the first sentence of the description is the most important, and Google notes that users may read only the first few sentences. Write that sentence as the answer to "what does this app do for me?" Both stores also let you test listing assets: product page optimization in App Store Connect and store listing experiments in Google Play Console. On the App Store you can additionally assign keywords to custom product pages so that a page built for a specific use case appears in search for those keywords instead of the default page.

Both stores use ratings and reviews in ranking, which is why the timing of the rating prompt is a product decision, not only a marketing one. On iOS you can prompt for a rating up to three times in a 365-day period using Apple's system API, and the summary rating is specific to each storefront. Ask after a user has completed something valuable, and respond to reviews in App Store Connect and Play Console; Google lists responding to users and addressing their issues among its discovery recommendations.

Localization is where Canadian and Japanese launches differ from a U.S. template. Apple's storefront table lists English (Canada) as the default language for Canada with French (Canada) as the additional supported language, and Japanese as the default for Japan with English (U.S.) as the additional language. Apple does not document how additional localizations are indexed for search, so treat claims about "extra keyword slots" with caution and localize for the people who will read the page. In Japan, that means researching the actual search terms, which may be written in katakana, kanji or English, rather than translating an English keyword list.

This is the order we work through when preparing a store listing for a first release. It front-loads the decisions that are slow to change, such as the name and category, and leaves the elements that can be updated at any time for after launch.