I received this message from Google Play, but it is not specified in it airtable
During review, we found that your app causes users to download or install apps from unknown sources outside of Google Play, which is not compliant with our Device and Network Abuse policy:
An app distributed via Google Play may not modify, replace, or update itself using any method other than Google Play’s update mechanism. Likewise, an app may not download executable code (e.g. dex, JAR, .so files) from a source other than Google Play. Please note that you are responsible for all aspects of your app; by using an SDK in your app, you are responsible for how that SDK behaves within your app.
Apps and app listings on Google Play must not provide any means to activate or access functionality that violate these terms, such as linking to a non-compliant APK hosted outside Google Play.