Samsung’s Wearable app breaks Google rules, sideloads Samsung Pay APK
Samsung has been sideloading the Samsung Pay APK from the Samsung Wearable app instead of the Google Play Store.
Samsung's various smartwatches need you to load several apps to have them functioning on non-Samsung devices and these include installing Samsung Pay on your phone as well. However, Samsung has been breaking Google's terms of service by attempting to sideload the Samsung Pay APK from the Wearable app.
This was first pointed out by Max Weinbach on Twitter when he was trying to set up Samsung Pay on the Galaxy Watch from his OnePlus 8 Pro. Weinbach saw that the Samsung Wearable app retrieves an APK for Samsung Pay and prompts the user to sideload it, he also pointed out that the APK was being pulled from a server.
It's a pretty well known thing by developers, @ArtemR had mentioned it as the reason why the APKMirror app couldn't list actual APKs.— Max Weinbach (@MaxWinebach) June 9, 2020
If the apk is part of the app package in assets or if the app builds and signs the app, it should be fine to be published to the Play Store.
Earlier, the Samsung Wearable app directed users to set up Samsung Pay from the Google Play Store. Now, Samsung is distributing the plug-in as an APK. This clearly breaks Google's guidelines as explained in the Google Play Developer Distribution Agreement's section 4.5 - “You may not use Google Play to distribute or make available any Product that has a purpose that facilitates the distribution of software applications and games for use on Android devices outside of Google Play”.
In situations like these, Google movies applications from the Play Store, but the Samsung Wearable app is still there for now. This might change later unless Samsung fixes things.