How to find your Device ID (UUID) for iOS Development
If you plan to develop an iPhone or iPad app, you will first need to register your device ID to the Apple Developer Portal. Sadly, this process isn’t as simple as it looks, so here are four different ways to get your UUID.
Option 1 – iTunes/Mac
If you prefer GUI interfaces, iTunes will do the trick. Plugin your phone and go to “Summary.” This isn’t obvious at all, but if you tap the invisible field (look at the red box), you will switch between different serial numbers. You will find one titled “UUID.”
Option 2 – Use a website or app
Using external sites like https://get.udid.io