Google Play Store has updated his Play Store version and has made some minor changes. The change stops the apps from bypassing Play Store updates. It means that apps have to display the Play Store page for downloading the updates. This does affect the apps like Facebook which has started the auto update feature in the app.
Thus, it’s done by passing the Google Play. Thus the change has just made the Facebook in-app update illegal. Now update from Facebook needs to be seen. Will it continue with the auto-update feature or change the same to comply with the newly changed Play Store policy.