Which unique device identifier do we have on iOS that does not change when an application is installed / removed / re-installed

Question

I want to be collecting both the installation event (on the new app) and the account creation event (on all the old apps).

To ensure uniqueness and prevent fraud (that is each installation should correspond to a unique device, and should remain the same event if the app is un-installed and re-installed again on the same device) we can use hardware identifiers that can survive uninstall.

On android phone IMEI can be used as unique identifier, but this solution is not repeatable on iOS as Apple does not give access to any hardware or unique identifier for privacy reason.

I tried the approaches proposed in the following links:

1. link1

2. link2

3. link3

   From link 1 & 3 I tried:

   let deviceID = UIDevice.current.identifierForVendor!.uuidString

But this does not provide a unique ID that will remain the same once the app is un-installed and re-installed again.

Please is there a better approach for me to handle this issue in swift. Thank you!

Answer 1

You can use Device Check API introduced in iOS 11, if you want to identify user's device even if user reinstalls your app.

Your server can use the generated token on the apple device. for more details please refer the following documentation

https://developer.apple.com/documentation/devicecheck/dcdevice/2902276-generatetoken