You are the owner of Apple device or you want to buy a phone from that company? Before you do that you should know its IMEI number.
 

IMEI number is a way to identify mobile device, you can use that number to check exact deatils of your phone, or to blacklist your device when it gets stolen. 
You should always check your IMEI number before buying new device, especially if you are going to buy used phone. 

Below you will find several methods of finding IMEI number of apple devices.

1. Using the Dial Pad
   Enter code *#06# in the dialing field of your phone.
   IMEI number should be instantly displayed on your screen.
2. 
    
3. In the phone menu
   Go to Settings and then General -> About
   
    
4. On the box
   You can find IMEI number of Aplle devices on your phone box.
    
5. On the SIM tray
   If you remove SIM cards you should see IMEI number labeled on SIM tray of your device.
    

Below you will find a video showing how to find IMEI number on the example of Apple iPhone X