Let's say I installed an app from the App Store, and my Apple ID is johndoe@gmail.com. Is it technically possible for the app developer (a random person, not an app developed by Apple) to see information such as:
App installed by johndoe@gmail.com 24 April 2015 at 12:05 PM
App uninstalled by johndoe@gmail.com 20 December 2016 at 2:08 PM
App reinstalled by johndoe@gmail.com 15 February 2017 at 5:53 PM
Or is gathering information on which Apple IDs installed your app blocked by iOS? (I use iOS 10.3.1 on iPhone 6).
Further, if I deleted an app (for example, a game), and reinstall it, will the app be able to infer that I had installed it before (assuming my dynamic IP has changed because I turned Airplane mode on and off (I use mobile internet), that I reset the Advertising ID under Settings–>Privacy–>Advertising, and no other apps by that developer are also installed on my device)?
Thanks!
PS – Sources for any answers you give would be much appreciated!
Best Answer
No, apps can't see your Apple ID unless you allow it. Pro Tip: use a unique email address for your Apple ID, that you use for no other purpose. Also use unique email addresses for each app or service that you don't completely trust (i.e., all of them).
Our Approach to Privacy
Yes, it is technically possible for apps to know that you previously had their app installed. This was the cause of the recent Uber controversy:
Uber responds to report that it tracked devices after its app was deleted
Unfortunately, it's very difficult for users to prevent this. At the least, from what I've been able to determine, you'd have to not use iCloud Keychain to share data across devices, and you'd have to factory wipe your phone and NOT restore it from a backup.
See also:
What unique fingerprinting information can an iOS 10 app collect?