The changelog of a popular SMS/MMS app, Textra, states:
Textra is now backed up automatically [emphasis added] using the built-in Google Backup service. Makes it so easy to swap devices or uninstall / reinstall without losing your settings and any customization! Supported from Android 6.
What does this really mean? In Android 7.0 is there a way to disable a single app from sharing private/personal data with Google? If not, how about all apps?
The app itself does not appear to have any options regarding this unwanted functionality.