Overview
The Play Integrity API helps protect your apps and games from potential risky and fraudulent interactions, such as cheating and unauthorized access, allowing you to respond with appropriate actions to prevent attacks and reduce abuse.
When your app or game is used on a device that runs Android 4.4 (API level 19) or higher, the Play Integrity API provides a signed and encrypted response that includes the following information:
Genuine app binary: Determine whether you're interacting with your unmodified binary that Google Play recognizes.
Genuine play install: Determine whether the current user account is licensed, which means that the user installed or paid for your app or game on Google Play.
Genuine Android device: This tells you whether your app is running on a genuine Android device powered by Google Play services.
Automated Play Integrity
Google Play adds runtime checks that are hard to remove. An auto generated code is added to the installable APKs as part of the publish process. The developers don't need to make changes to their code, and protections work without a data connection.
Impact on 3rd Party Stores\Installers
When installing an app from source other than the Play Store, the Genuine play install check will result in poor user experience as described below:
How to exempt 3rd Party Stores\Installers from this check?
After checking the “Enable the automatic integrity protection for your app” checkbox:
The following section will be displayed:
You should uncheck the “Require installation from Google Play” checkbox and publish a new version.
As mentioned in the screenshot above, unchecking the “Require installation from Google Play” checkbox will disable ONLY the installation source restriction in contrast to the “Restrict modification” and “Restrict reverse-engineering” that are always applied.
In general, installation out of Google Play can be an indication of unwanted behavior, nonetheless this checkbox is directed for app developers that do aim to distribute their app on trusted stores and trusted channels other than Google Play
Please visit this link (from Google’s documentation) for further information about the Automated Integrity Protection and the “Require installation from Google Play” checkbox