The latest version of Apple’s iOS system for iPhones will prompt users to choose whether or not they want each individual app installed on their mobile devices to track their personal data. This feature will only operate if a user enables it under Settings . . . Privacy . . .Tracking:
If an app receives permission to collect personal data, the device’s ID; the advertising ID; the user’s name; and the user’s email address will be used in conjunction with data from third parties to send you targeted advertising. Apple’s notice for its Transparency Tracking feature warns that when permission to track is given “[t]he app developer may also choose to share the information with data brokers which may result in the linking of publicly available and other information about you or your device.”
Notably the notice acknowledges that this feature does not prevent an app dev from using your personal data to send you targeted ads on the iPhone. The restriction only applies to using the data to target you elsewhere.
After the feature is enabled when you open an app, you’ll get a notice like this;
You set the option to turn off personal data collection for use off your iPhone:
Oddly, on my iPhone some apps such as Amazon and Google Maps do not prompt the user to respond to the tracking transparency feature.