Configuration of the device (including first time use), enabling and disabling features provided by carriers. I believe it's only useful if you want to use a Sprint service with a non branded phone (not sure at all) https://www.androidpolice.com/2015/03/10/android-5-1-includes-new-carrier-provisioning-api-allows-carriers-easier-methods-of-setting-up-services-on-devices-they-dont-control/ Displays annoying notifications if you unlocked your bootloader
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