Your app store listing is your most important marketing asset for organic downloads. A properly optimised listing ranks higher in store search, converts more browsers into downloaders, and costs nothing beyond the time to optimise it.
ASO has two distinct goals that require different optimisation strategies. The first is ranking — appearing high in search results when people search for apps like yours. The second is conversion — convincing people who see your listing to download your app. Both matter equally, but they are optimised differently.
The iOS subtitle gives you 30 additional characters that carry ranking weight almost as strong as the title. Most apps leave this empty — a major missed opportunity. Use it for your secondary keyword that did not fit in the title.
Screenshots without text callouts underperform against screenshots that highlight specific features. Add 3-5 word feature callouts to each screenshot. A/B test with Apple's Product Page Optimisation or Google's Store Listing Experiments.
Apps with preview videos convert significantly better than those without. A 15-30 second video showing the app in use — not a flashy animation — is the highest-impact conversion improvement available to most apps.
Apps where developers respond to reviews — especially negative ones — show higher conversion rates. Responses signal that the app is actively maintained and that issues get resolved.