App optimization means improving the experience from discovery to a completed task. Start by finding where people get stuck: they cannot find the app, they leave the listing without installing, or they cannot finish a task after installation. A faster launch will not fix an unclear store promise; a better screenshot will not fix a crash.
This checklist covers 15 concrete checks across performance, user experience and the store listing. It does not predict a download increase. Use it alongside the download-growth diagnosis guide when you need to choose the first problem to address.
Choose the bottleneck before changing the app
| Observed problem | First checks | Outcome to measure |
|---|---|---|
| Relevant people rarely see the listing | Availability, relevant search phrases, acquisition sources | Qualified listing exposure in one market |
| Visitors leave without installing | Promise, actual UI, rating concerns, price expectations | Store-reported acquisition conversion for the same source |
| Installs do not become useful sessions | Startup, crashes, sign-in, first task | Completed first task per new-user cohort |
| Users do not return | Unresolved failures, recurring need, saved work | Repeat task or retention at a relevant interval |
Write down the app version, device range, store, country, dates and acquisition source before measuring. Keep downloads, first opens and paying customers separate. Compare similar groups before and after the change. A shift in countries, devices or traffic sources can make a result look better even when the product has not improved.
1. Measure cold startup on actual devices
Test a fresh launch with an empty cache as well as a warm launch. Record the time until the first useful screen responds, then inspect what must finish before that can happen. Authentication refresh, configuration requests, database migrations and analytics SDK initialization can all block that path.
Use the platform profiler and release-like builds, including a lower-powered device you support. Repeat the measurement across several sessions and report the range, not just the fastest run. Keep the same start and end events when comparing versions.
2. Defer work that is not needed for the first task
Load optional assets and secondary features when they are needed. Where your framework supports code splitting, check that it actually reduces startup work; shipping another bundle is not itself a performance result. Handle failed deferred loads with a useful retry state.
For example, a budgeting app can show saved balances before refreshing optional category illustrations. It still needs to make clear when account data is stale. Speed should not hide missing or outdated information.
3. Reduce transfer size without breaking quality
Inspect your release artifact for duplicate assets, unused resources and unexpectedly large dependencies. Keep symbol files available to crash reporting even when they are distributed separately from the customer build. Verify any shrinking or optimization setting against a release build, because reflection and generated code may need additional configuration.
Size limits and delivery options vary by platform and distribution method. Check the current store submission requirements rather than relying on old cellular-download thresholds. A useful engineering target is the measured time and reliability of installation on the networks your users have.
4. Match images to their rendered size
Decode images near the size they will be displayed, use appropriate compression, and inspect text and fine detail after export. Measure both download bytes and decoded memory: a small compressed file can still be expensive once loaded.
Use native vector assets for simple shapes when appropriate. Test format support on your minimum OS version. Avoid declaring one image format the winner for every screen; artwork, transparency, decoding cost and visual fidelity can change the decision.
5. Make caching and offline states explicit
Cache data that is safe to reuse and decide when it expires. A read-only saved note and a current bank balance need different policies. Show last-updated information where freshness matters, and clear account-specific cache on sign-out when appropriate.
Test airplane mode, connection changes and a request that never completes. Preserve user input and give a specific recovery action. Check that retries do not duplicate purchases, uploads or other writes.
6. Fix crashes and unresponsive sessions before expanding acquisition
Group failures by affected users, app version and device. Prioritize repeated failures in the first task, even if a less important screen produces more raw logs. Verify the fix in a new release and check whether the affected population improves.
Google documents that core Android vitals can affect Play visibility. Use its current console thresholds and device breakdowns. Those reports help you diagnose affected Android users; they do not provide a ranking formula for both stores.
7. Give people a short route to the first useful result
Define the first task in plain language: save a note, complete a workout, create an invoice, or understand a balance. Remove setup that is unnecessary for that task. If an account or permission is required, explain the reason at the moment it becomes relevant.
Do not assume every app needs a multi-screen tour. Observe someone attempting the task, record where they hesitate, and improve those moments. An onboarding completion event is useful only if the person can then use the product.
8. Make controls understandable and accessible
Check text scaling, screen-reader labels, focus order, contrast and touch targets. Communicate loading, success and errors in more than color alone. Make disabled controls explain what is missing instead of leaving the person to guess.
Test the full task using the platform accessibility tools. Include forms, dialogs, payments and error recovery in that check, as well as the welcome screen.
9. Capture a store-listing baseline
Record your current title, descriptions, screenshots, country and selected search terms. Save a screenshot of the live listing, because an approved edit and a publicly visible update are different states. Our ASO report template gives you a place to log the baseline and the next decision.
A free listing scorecard can flag fields to inspect. Treat its score as a checklist generated by one tool, not an Apple or Google score or a forecast of downloads.
10. Match metadata to the app's actual job
Choose search phrases that describe a task the current app can complete. Check the results in your target storefront: an ambiguous term may lead to a different category of product. Keep the app name readable and avoid repeated claims or competitor trademarks.
Use metadata generation to prepare alternatives from an accurate app brief, then review the wording and field limits. Review the draft before sending it through the store's submission process.
11. Build screenshots around proof
Make each image answer one question: what can I do, what does the result look like, or why is this relevant to me? Show current UI at readable size. A fictional balance or sample project is fine when it is identified as an example; it is not customer evidence.
Start with a coherent campaign in the screenshot editor. Free templates support manual editing and export with a free account; Pro collections have their own access requirements and AI work can use tokens. Check the final exported image at the size a store visitor will see it.
12. Test one clear creative hypothesis
Compare a meaningful message change, such as showing the completed task before the setup screen. Keep a control and avoid changing every asset at once if you want to learn which choice mattered. Use the store's experiment report and record uncertainty as well as the estimate.
Apple's product page optimization supports tests of icons, screenshots and app previews. A before-and-after keyword observation is a different kind of evidence and should not be labeled a randomized conversion experiment.
13. Localize one supported market completely
Choose a market using relevant traffic, demand, product availability and support capacity. Translate the promise, screenshots and necessary in-app experience together. Have a fluent reviewer check language, currency, examples and any claims.
The metadata translation workflow can prepare drafts in supported languages. Review the quoted cost and the actual localized result. Adding a locale does not produce a fixed revenue increase.
14. Ask for feedback about a specific friction point
After a failed or completed task, a short optional question can reveal why the person struggled. Ask about what happened, not whether they agree your redesign is better. Combine feedback with error logs and funnel data rather than treating one response as representative.
If you use session recording, verify consent, data handling and sensitive-field masking before collecting it. You can often diagnose a problem with an error event or an observed usability session without recording every customer action.
15. Keep an experiment log and decide what to do next
For each change, record the problem, what you expect the fix to do, who owns it and when it ships. Note which users are affected, what you will measure and when you will review the result. Keep an old asset or configuration available when reversal is practical. Log concurrent releases, campaigns and seasonal changes.
If the outcome is inconclusive, say so. Decide whether to collect more data, run a narrower test or work on a larger bottleneck. The best next optimization is the one your current evidence supports, not the next item in a generic checklist.
Frequently asked questions
What is the difference between app optimization and ASO?
App optimization includes performance, usability and the path to useful work. ASO focuses on discovery and conversion within app stores. They overlap when the listing promise affects the experience after installation.
Which app optimization task should I do first?
Start with the largest observed barrier to useful work. Fix critical crashes and broken first tasks before increasing acquisition. If the app works but relevant visitors are scarce, inspect availability and listing discoverability.
Can these changes guarantee more downloads?
No. Outcomes depend on the app, audience, traffic and execution. Measure a defined baseline and follow-up, or use an appropriate controlled experiment, rather than assuming a fixed percentage lift.
