Google Play has a limit of 50 MB on their APK files, therefore the mag+ MIB file cannot be included in the app build as it is with iOS and Amazon apps. Instead, it must be uploaded as an “APK extension” file directly to Google Play. This means that the MIB is hosted by Google and mag+ does not control the MIB in any way.
Single-Issue apps will check for the Google Play extension file every time the app is launched and will start downloading the file if not already downloaded.
Note: Single-Issue apps do not incorporate in-app billing. If there should be a cost associated with the content, it should be placed on the app itself and not the issue within the app.
Important Requirements and Rules
- Each expansion file can be no larger than 2GB.
- In order to download your expansion files from Google Play, the user must acquire your application from Google Play -- Google Play will not provide the URLs for your expansion files if the application was installed by other means.
- If you update your application with a new APK or upload multiple APKs for the same application, you can select expansion files that you've uploaded for a previous APK.
- You cannot issue an update to your application by changing the expansion files alone—you must upload a new APK to update your app.
- When updating an expansion file manually, you must delete the previous expansion file.
- See this article on Expansion Files for a full list of rules and requirements.
Testing your Extension File
2. Set up your application in Google Play.
3. Upload your APK using the Google Play Developer Console.
During this process, add your MIB file as an expansion file.
Note: Sometimes you must upload your APK twice before the option to add an expansion file appears. This is a known bug in Google Play.
4. Fill in the necessary application details in Google Play (title, screenshots, etc).
Note: You can come back and finalize these details before publishing your application.
5. Click the "Save" button.
Note: Do NOT click "Publish." Clicking "Save" saves the application as a draft so that your application is not published for Google Play users, but the expansion files are available for you to test the download process. Make sure that the status of your application actually says "draft."
6. To test your app, install the APK from the mag+ Publish portal on your device.
7. Launch the app on your test device.
8. Agree to download the content.
You will be greeted with the dialog “This app requires X MB of extra data, do you wish to download now?”
Note: The app cannot be started without the expansion file, so if the user does not download the file, the app will shut down and the dialog will re-appear upon the following startup.