An incident occurred in which the same device token was sent from different IDFVs.
To investigate the cause, please let me know the informations below.
・What are the conditions under which the IDFV changes?
・When an IDFV changes due to uninstallation, etc., does the device token always change?
・Is there a chance that a device token that has been used in the past in another terminal will be used in another IDFV terminal?
This is entirely possible. Push tokens are based on an app's bundle ID, and as long as the app has not been removed from a device between installations, it will remain the same regardless of who (which team) owns or has built the app.
IDFV on the other hand can change if certain aspects of the app or the installed bundle changes. The value can change when installing test builds using Xcode or when installing an app on a device using ad-hoc distribution. The identifier will also change if certain metadata about an app installed from the App Store has changed, like the name of the publishing team.
If the IDFV changes due to an uninstallation, the token will also change. Two device/app installation combinations getting the same token is highly unlikely, albeit being non-zero.
Argun Tekant / DTS Engineer / Core Technologies
