Once you have completed building your Unreal Engine 4 (UE4) powered mobile project, the next step is getting it ready to be distributed through the Google Play store. In the following document, we will take a look at some of the various items that could cause issues when getting your UE4 project on the Google Play store.
The Google Play store changes its look, layout, and workflows on a regular basis without any prior notification. Because of this, some of the information in this guide might be in a different location, use a different name or been removed completely. Make sure to check the official Google Play Store help pages should you not be able to find the information you are looking for, or if the information you found is out of date.
Google Play Console
The Google Play Console is the web portal that is used to upload, manage and release your UE4 project on the Google Play Store. From the Google Play Console, you can do a wide range of tasks, like configuring your project for release to running automated tests. You can track how you are acquiring new users or how well your UE4 project is performing across a wide range of Android capable hardware.
Google Play Store Listing
Before your project can be displayed and downloaded from the Google Play Store, you will need to first fill out all of the various sections that have a grayed out checkmark box in the Dashboard section of the Google Play Console.
Make sure to read each section carefully and provide the needed information and files.
Once you have successfully completed a section the grayed out checkmark box will change to green like in the following image:
Once each of the required sections in the Dashboard has a green checkmark next to it, your application is then ready to be reviewed by Google for release on the Google Play Store.
Google Play Store APK Size
The Google Play Store has a size limit of 100 MB for any APK that is uploaded. If your application requires more data than can fit in the 100 MB limit, you will have to place the rest of the content into an Opaque binary blob(OBB)file. The maximum size for an OBB is 2 GB. Once you have uploaded your UE4 APK to the Google Play Console, it can take at least 45 minutes or more until you will be able to push the APK into Alpha, Beta or Release. Because of this, it is common practice to complete App Releases section first and then fill out the rest of the needed information.
Google Play Console API Changes
Google Play will require that new apps target at least Android 8.0 (API level 26) from August 1, 2018, and that app updates target Android 8.0 from November 1, 2018. UE4 version 4.21 or newer will take this into account but any project made with previous versions of UE4 will have to be updated to accommodate for this new change.
This new change will require that your UE4 project ask the user for permissions to utilize certain features of the OS, like writing a save file to disk, when it is time to do so. In the past, the user was asked to grant all needed permissions when the application was first to run. To help you manage the requesting of permission in UE4, version 4.21 (and later), you will need to use the Android Runtime Permission Plugin that can be found in the Android section of the Plugins menu.
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Project SDK Override
The Project SDK Override enables you to change, on a per project basis, which version of the Android SDK's are used to compile your project. You can find these options by going to Project Settings \> Android \> Project SDK Override.
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Android SDK Version
The Android Minimum SDK Version input helps determine the minimum OS version that your app can be installed on. The Target SDK Version informs the Android OS of the expected behavior of the API. If you are not sure which SDK Version is used with which Android OS, check out the Codenames, Tags, and Build Numbers page for more information.
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| Setting | Description |
|---|---|
| Minimum SDK Version | This controls the minimum OS version that an app can be installed on. This is also used by the Google Play Store to filter which devices your application is seen by in the store. |
| Target SDK Version | This informs the Android OS of the expected behavior of the API. Setting this to a particular API level is a promise that your code will work with the features and changes introduced by that Android release. |
If you have a project that is using an older version of UE4 and you want to ship to Google Play store, you will need to set your Target SDK to 26. This will still allow your app to run on older devices that might not have Android SDK 26 as long as the Minimum SDK Version is sufficient.
Shipping with Multiple Expansion Files
The Unreal Engine automatically packages the contents of the Content folder into separate OBB expansion files when you package your project for Android. When publishing an application to the Google Play Store that uses multiple OBB files, follow the steps below to ensure that your OBBs are uploaded correctly alongside your project's APK:
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Start a new Alpha track by pressing the Create Release button.
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Press the Browse Files button to upload your APKs. You should upload your Arm7 first, then your Arm64 second.
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Once the upload is complete, press the Plus icon located next to the word REMOVE to add your OBB file.
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From the OBB Menu, click the drop-down next to the No Expansion File option and from the displayed list, select the Upload a New File option.
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Using the displayed dialog box, navigate to the OBB that matches the APK store version and press the Okay button.
If you are not sure what APK store version you should use, you can open your BAT files with a text editor to see which version your project is using.
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Once the OBB has been uploaded, you will see it in the Use Expansion File box. Press the Save buitton.
When uploading an OBB file output with UE version 4.22 or earlier, you may receive a warning indicating that the file you have uploaded is identical to an earlier one, as in the above image. This can occur if the OBB file that you are using has the same size in bytes as an OBB from a previous build that you have uploaded. However, the OBBs are not actually identical, and if you select earlier OBBs then it will result in errors when attempting to run the application. Ignore this warning and upload the OBBs output with your build as normal.
If you are using UE version 4.23 or later, this issue is resolved and the upload dialogue will not erroneously report OBBs as being identical.
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Repeat the above steps for any additional OBB files you might have.