Your Mac, iPhone and iPad all have an assigned Universal Unique Identifier (UUID). These codes are specific to each device and, similar to a serial number, are used by developers to identify them individually. Here is what you need to know.
What's a UUID?
A UUID is a string of letters and numbers that forms a unique pattern. Your Mac, iPhone and iPad each have a UUID, and no other device shares it. This sounds like a serial number in this regard, but if the numbers are used to identify your device by Apple and your mobile carrier, developers typically use the UUID instead.
Normally, you do not need to know (or access) your UUID. However, if you register a device as part of the Apple Developer Program to install beta software, you will need it. Application developers can also request the UUID of your device so that you can provide versions that will only work on that device.
How to find the UUID of your Mac
Click the Apple logo in the menu bar, and then click the "About This Mac" option.
Click the "System Report" button.
Note the text next to the UUID material.
You can copy the text directly from the window, if necessary.
How to find the UUID of your iPhone and iPad
Connect your iPhone or iPad to your computer and open iTunes. Click on the device icon at the top.
The UUID of your device is hidden by default. Click on "Serial Number". It will change to display your UUID.
You can also copy the UUID directly from iTunes.
Other identifiers to note
You can also meet other identifiers.
Template identifiers are used to highlight the model of a particular device. These are not unique to this device, but rather to the model band in which it falls. For example, an iPhone 7 is called iPhone9, x, while an iPhone XS is iPhone11, x. These numbers are normally only used by Apple, but they sometimes show up in leaks for upcoming devices.
Apple and its suppliers use model numbers to identify the devices and the market for which they were designed. For example, an iPhone XS sold in the United States is the A1920, while another sold in Japan is the A2098.
IMEI numbers, also known as the International Mobile Equipment Identification Number, are used by operators. They are unique to any device that connects to the cellular network and are often used to block devices. reported as stolen or lost.