This appears to be factually incorrect both for apps installed from third-party app stores and from Google Play itself. See "Alternative billing systems for us

This appears to be factually incorrect both for apps installed from third-party app stores and from Google Play itself. See "Alternative billing systems for users" on https://support.google.com/googleplay/answer/11174377?hl=en-US https://support.google.com/googleplay/answer/11174377?hl=en-...