How to find your iOS Device UDID
In order to become an iOS beta tester, you must provide your device’s UDID to Datalink.
To do this, you can plug your device into your computer and use iTunes to obtain the UDID.
Finding your UDID in macOS 10.15 Catalina
Your UDID can be found in Finder. In the Finder sidebar, choose your iPhone, then click area in the header just under your phone’s name until you can see the UDID. Then, right click and choose Copy UDID.
Finding your UDID in macOS 10.14 Mojave
Open iTunes.
Plug in your iPhone, iPod touch or iPad.
Click the device icon that’s near the top left of the window.
Ensure you’re on the Summary tab.
Click on the text that says Serial Number. It should change to say UDID.
Select Copy from the Edit menu.
Your UDID is now in the clipboard, so you can paste it into an email or message.
Finding your UDID in macOS 10.13 High Sierra and prior
Open iTunes.
Plug in your iPhone, iPod touch or iPad.
Click its name under the devices list.
Ensure you’re on the Summary tab.
Click on the text that says Serial Number. It should change to say Identifier (UDID).
Select Copy from the Edit menu.
Your UDID is now in the clipboard, so you can paste it into an email or message.
Finding your UDID on Windows
Open iTunes.
Plug in your iPhone, iPod touch or iPad.
Click its name under the devices list.
Ensure you’re on the Summary tab.
Click on the text that says Serial Number. It should change to say Identifier (UDID).
Select Copy from the Edit menu.
Your UDID is now in the clipboard, so you can paste it into an email or message.