U DID, but now you don’t
Every iPad and iPhone has a unique identifier, or UDID (Unique Device IDentifier), a 40 character string that is hard-coded to each, individual device.
It looks something like this:
a004e3409a473b2034d899d246…
Since the early days of iPhone development, it’s been common practice for developers to use the UDID to associate devices with end-users, and for use in analytics, security, [...]