How good is this protection? If it's any good I bet it'll only apply to the latest version of Android & or Google purchased devices.
Good question and worth keeping an eye on until knowing for sure which Android version supports it. So far mine are Jellybean, Lollipop, and Marshmallow. I like all 3.
Basically, they are just making their built-in security features more visible. They have had background scanning known as "Verify Apps" and "Find My Device" (previously known as "Android Device Manager") all these while... https://blog.google/products/android/google-play-protect/
http://www.androidpolice.com/2017/0...s-googles-app-scanning-foreground-play-store/ Play Protect's appearance in the Google Play app is Google's way of bringing their existing screening process to the foreground of your experience