How iOS app get IMEI and other device's information from MDM server?

Our team already create a MDM server, and get the device's information after it register to MDM server. But now the problem is: how can I get the device's information (like IMEI) back to our application(app)?

I've search some method, that mention MDM server can 'push' a dictionary to the app's NSUserDefaults container. How does this work?

I'm really new to this field :( Please give me some hints, Thanks a lot!

How iOS app get IMEI and other device's information from MDM server?
 
 
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