How to Create an AAB File for Google Play (Android Studio)
Step by step: generate a signed Android App Bundle in Android Studio or with Gradle, then upload it to Play Console.
Read the guide →How to Publish a Kodular App on Google Play (2026)
Quick answer To publish a Kodular app on Google Play, build an Android App Bundle (.aab) in Kodular, download and back up your keystore, create the app in Play Console, upload the bundle, complete the store forms, run the 12-tester closed test if your account needs it, and apply for production.
Kodular makes it easy to build an Android app without code, but the part after the build is where most beginners get stuck: the AAB file, the keystore, Play App Signing, the store forms and the closed test. This guide walks through the whole route from Kodular project to a published app, in plain language and in the right order.
Can you publish a Kodular app on Google Play?
Yes. A Kodular app is a normal Android app once it is built, so you can publish a Kodular app on Google Play like any other. You build an Android App Bundle in Kodular, create the app in Google Play Console, upload the bundle, complete the store forms and release it. If your developer account is new, you also have to finish the closed test first.
The steps themselves are not hard. What trips people up is the order, and a few files you cannot afford to lose. Follow the order below and you avoid the usual errors.
A note on accuracy: Kodular changes its menus from time to time, so we describe what each option does rather than promising an exact button name. Google's rules are quoted from its Help pages in the sources at the end.
What do you need before you start?
| Item | Why you need it | Guide |
|---|---|---|
| A Google Play developer account | One-time US$25 fee plus identity verification | Developer account fee |
| A finished, tested app | Install it on a real phone first. Crashes lead to rejection. | Why apps get rejected |
| A final package name | It cannot be changed after you publish | AAB file guide |
| App icon (512 x 512) and screenshots | Required for the store listing | First publish guide |
| A privacy policy URL | Needed for the Data safety form, and always if you use ads | Data safety and privacy policy |
| 12 testers for 14 days | Required for many new personal accounts | How to get 12 testers |
If you use AdMob, set that up after the first release, not before. Our guide on AdMob ads not showing in a new app explains the timing.
How do you build the AAB in Kodular?
Since August 2021 Google Play requires new apps to be published as an Android App Bundle, not an APK. In Kodular Creator, use the build option that produces an .aab file, not the one that produces an .apk. The APK is still useful for installing the app on your own phone to test it.
- Set the versionCheck the version code and version name in your project properties. Each upload to Play Console needs a higher version code than the last.
- Check the package nameMake sure it is final, unique and in the form com.yourname.appname. It identifies your app forever.
- Build the bundleChoose the Android App Bundle (.aab) build option and wait for Kodular to finish.
- Download the AABSave the file somewhere you can find it, for example a folder named after your app and version.
- Download the keystoreKodular's own community tutorial on signing an AAB tells you to download your application's keystore from Kodular. Do this now and store two copies.
For a deeper look at the file itself, read how to create an AAB file for Google Play. Google explains the format in the Android App Bundle documentation.
Protect the keystore: The keystore and its passwords prove that updates come from you. Do not email them, do not post them in a forum and do not keep the only copy on one laptop.
How does the keystore work with Play App Signing?
Google Play uses two keys. The upload key is the one you keep and use to sign your bundle before uploading. The app signing key is the one Google holds and uses to sign the apps it sends to users. Google recommends that the two keys are different. Our full explanation is in Play App Signing explained.
In practice there are two situations:
| Situation | What you do | Watch out for |
|---|---|---|
| First time publishing this app | Opt in to Play App Signing when you create the release and let Google generate the app signing key. Your Kodular keystore acts as your upload key. | Keep the keystore safe. It is how you prove updates are yours. |
| You already distributed this app with a keystore (for example an APK on another store) | Use the option to export and upload an existing key from a Java keystore. Kodular's community tutorial describes this route using Google's PEPK tool. | Follow Google's current instructions carefully, because a mistake here is hard to undo. |
One error shows up often in Kodular forum posts: “You uploaded an APK or Android App Bundle signed with a key that is also used to sign APKs sent to users.” One Kodular community thread reports exactly that message when uploading with Play App Signing on. The message says the bundle was signed with a key that Google already uses for the apps it distributes. Because Google recommends separate upload and app signing keys, the fix is to sign the bundle with a different upload key and register that key in Play Console. If you cannot choose a different keystore in your Kodular build, ask in the Kodular community, where staff and users share the current method.
How do you create the app and upload the bundle?
- Create the appIn Play Console choose Create app. Enter the name, default language, App or Game, and Free or Paid. Free apps cannot be turned into paid apps later, so decide now.
- Complete the Dashboard tasksPlay Console lists the setup tasks under the Dashboard. Work through them in order. The next section shows what they are.
- Create a closed testing releaseGo to Testing > Closed testing, create a release on a track, accept Play App Signing and upload your AAB.
- Add release notes and roll outWrite a short note about what is in this version, review the release and roll it out to the closed track.
- Add testers and share the linkCreate the tester list and share the opt-in link. See how to add testers and how to share the link.
Which store forms must you complete?
Most rejections come from forms that are rushed or that contradict each other. Fill them in carefully, and make sure the answers match what the app really does.
| Form | What it asks | Guide |
|---|---|---|
| App access | Whether reviewers need a login or special steps | App access instructions |
| Ads | Whether your app contains ads. A Kodular app with AdMob blocks does. | AdMob guide |
| Content rating | A questionnaire that gives your app an age rating | Content rating questionnaire |
| Target audience | Who the app is for, including whether children are included | Target audience |
| Data safety | What data the app and its components collect | Data safety form |
Kodular components and extensions can collect data or contact servers, for example ads, analytics or cloud databases. Go through the components you actually use before you answer the Data safety form.
How do you run the closed test for a Kodular app?
The closed test works the same for any app. Google requires personal developer accounts created after November 13, 2023 to run a closed test with at least 12 testers who stay opted in for at least 14 days in a row, then apply for production. Details are in the 14-day requirement explained.
- Ask for 15 or more testers so a few drop-outs do not stop you. More about finding testers.
- Ask testers to open the app on different days and report anything that breaks.
- If you fix a bug, build a new AAB with a higher version code and upload it. How to update an app.
- Keep notes of the feedback you got and what you changed. The production access questionnaire asks for it.
When the 14 days are over, follow how to apply for production access. If you cannot find the button, this guide explains why.
What are the common Kodular publishing errors?
| Message or symptom | Likely cause | Fix |
|---|---|---|
| Play Console does not accept the upload as a new app | You uploaded an APK, not an AAB | Build the .aab option and upload that |
| Version code has already been used | You re-uploaded without raising the version | Increase the version code in your project and build again |
| Package name already exists | Another app on Google Play uses it | Choose a unique package name before the first release |
| Signed with a key also used for APKs sent to users | Upload key and app signing key are the same | Use a separate upload key (see the signing section above) |
| Signed with the wrong key | A different keystore than the registered upload key | Use the original keystore or request an upload key reset |
| Target API level warning | Google requires apps to target a recent Android API level | Check Kodular's announcements. The build target depends on the version of Kodular's builder. |
| Rejected for Data safety mismatch | The form does not match what your components do | Review the components, then correct the form |
More fixes are in Google Play app rejected: reasons and fixes.
How long does the whole process take?
| Stage | Typical time | Notes |
|---|---|---|
| Developer account verification | Varies | Verification guide |
| Build, upload, forms | A few hours to a day | Faster if the app is already tested |
| Closed test | At least 14 days | Counted from when testers opt in |
| Google's review of your production application | Usually seven days or less, sometimes longer | How long production access takes |
Plan on three to four weeks from the day you upload to the day the app is live, and start the closed test as early as you can.
Part of a series: this article is one chapter of Google Play Closed Testing: The Complete Guide. Start there for the full roadmap from setup to production.
Sources
- Google Play Console Help: use Play App Signing
- Google Play Console Help: app testing requirements for new personal developer accounts
- Android Developers: about Android App Bundles
- Kodular Community: signing an AAB file tutorial
- Kodular Community: problem with app bundle signed
Frequently asked questions
Does Kodular publish my app to Google Play for me?
No. Kodular builds the file. You create the app in Play Console, upload the Android App Bundle yourself, complete the store forms and run the release.
Can I upload an APK from Kodular instead of an AAB?
For new apps Google Play requires an Android App Bundle (.aab). An APK is fine for installing on your own phone, but Play Console will not accept it for a new app.
Where do I find my Kodular keystore?
Kodular's community tutorial on signing an AAB tells you to download your project's keystore from Kodular. Download it once, store copies in two safe places and never share it.
What if I lose my Kodular keystore?
With Play App Signing, Google says a lost or compromised upload key can be reset: you create a new key and send a reset request in Play Console. It takes time, so back up the keystore now.
Do I need 12 testers for a Kodular app?
Kodular makes no difference. The requirement depends on your Google Play developer account: personal accounts created after November 13, 2023 must run a closed test with at least 12 testers opted in for 14 days in a row.
Do I need to pay for a developer account?
Yes. Google charges a one-time registration fee of US$25, then you verify your identity before you can publish.
