What Is ASO (App Store Optimization)?

ASO (App Store Optimization) applies SEO logic to a store's internal search engine. Instead of optimizing for Google, it optimizes for ranking among the first results when someone types "photo editor" or a competitor's name into the App Store or Google Play. The goal has two parts: rank higher in that search, and get whoever lands on the listing to decide to install.

The most common mistake is treating ASO as a single technique. It's actually two separate exercises sharing one name. The first works the text fields each algorithm evaluates, title, subtitle, keywords, and decides whether the app lands at position three or position fifteen of a search. The second works the listing's visual elements, icon, screenshots, preview video, ratings, and decides what share of the people who see that listing tap "install." Optimizing only the first can drive more listing views without more installs. Optimizing only the second leaves a convincing listing that almost nobody finds.

The App Store and Google Play account for most of the searches that happen inside an app store, and in both, internal search works as a discovery channel independent from paid campaigns and editorial features. That's why ASO gets treated as an acquisition channel in its own right, not an add-on to web SEO, even though the two disciplines share much of their keyword research logic.

The difference with the biggest practical impact sits in the long description. A keyword-dense text helps ranking on Google Play and does nothing for ranking on the App Store, where it only serves a persuasive purpose. Copying the same copy strategy across both stores either wastes Apple's keyword field or overloads a description that, on Google, actually counts toward search.

On the App Store, Apple confirms that text relevance for ranking is based on matches with the title, subtitle, keyword field, and primary category. The keyword field is invisible to users, gets filled in through App Store Connect, allows up to 100 comma-separated characters with no spaces, and that's where research into terms that don't fit in the title or subtitle should land. Apple recommends not repeating words already covered by the title, subtitle, or category there, since they add no extra coverage.

Google Play has no separate keyword field. The app name (30 characters), short description (80 characters), and long description (4,000 characters) are the three text fields available, and all three come into play for keyword research. Google explicitly warns against repetitive or irrelevant keyword use in the app name, description, or promotional description, a sign that these fields do influence how the algorithm connects a listing to a search, even though Google doesn't publish the exact weight of each one.

That asymmetry changes how the work should be split between the two stores. An ASO team that only reviews the title and screenshots is optimizing just the visible half of the problem on Android, because it leaves out a long description that Google Play's search actually reads. On iOS, that same team gives up ranking opportunities if it doesn't fully use the 100 characters of the hidden keyword field, a space that never competes with the listing's visual appeal because the user never sees it.

Once the listing shows up in search, what decides whether that person installs stops being the ranking algorithm and becomes the design of the listing itself. The icon is the first filter: it appears as a thumbnail in the results list before the user opens the full listing, and a confusing or undifferentiated icon gets scrolled past before the app even gets a chance to show itself in full.

Inside the listing, the first two or three screenshots capture most of the attention, since they're the only ones visible without swiping on many devices. The preview video, when there is one, autoplays in some contexts and competes directly with the screenshots for that same initial space. Ratings and review counts act as social proof: a high rating count with a solid average lowers the friction of installing something unfamiliar, and a recent dip in rating usually carries more weight than a high historical average.

Both Apple and Google offer official testing tools for this second block. Apple's Product Page Optimization lets teams launch up to three alternative variants of icon, screenshots, or video against the current version, split traffic between them, and measure each variant's conversion with a statistical confidence level before rolling the change out to everyone. Google Play's Store listing experiments does the equivalent with the icon, feature graphic, screenshots, and copy, including the option to test localized variants across several languages at once. Neither tool touches ranking: both measure only how many people install, not where the listing ranks.

• Treat Apple's keyword field and Google Play's long description as two separate keyword research exercises, not the same copy pasted into both stores.
• Prioritize the first two or three screenshots: most users see only those without swiping, so that's where the message with the most weight in the install decision belongs.
• Use Product Page Optimization or Store listing experiments before launching a full listing redesign, instead of changing it blindly and waiting to see what happens to installs.
• Localize the title, subtitle or short description, and screenshots for each relevant market, rather than translating the same source copy without adapting local search terms.
• Respond to recent negative reviews reasonably fast: they weigh more heavily on the install decision than a high but old average rating.
• Track the listing's CTR in search results separately from the post-click install rate, since the two metrics respond to different levers.

• Filling Apple's keyword field with words already covered by the title or subtitle, gaining no extra coverage.
• Reusing the same short description meant for the iOS subtitle on Google Play, ignoring that Android's long description actually counts toward ranking.
• Changing the icon or screenshots without testing first, then blaming a drop in installs on a ranking problem when it was actually a conversion problem.
• Stuffing the promotional text or what's new notes with a keyword list, assuming it moves the App Store ranking the same way it does on Google Play.
• Leaving screenshots or video unlocalized in markets where the source language isn't dominant, losing conversion even when ranking is solid.