How to store local data after user delete my iOS app?

Question

I thought it\'s impossible, because all the data store in a sandbox, when user delete the app, all the data should be removed from the device.

But somehow, this happ

Answer 1

This is done using the keychain on iOS most likely.

Read up on it here: https://developer.apple.com/library/mac/documentation/security/Reference/keychainservices/Reference/reference.html