From their web page:You will be part of the Custom Experience program unless you opt out. You must opt in to the Custom Experience Plus program to be a part of it unless you are already participating in Verizon Selects. Verizon Selects participants will automatically be included.
Custom Experience uses information about the websites you visit and the apps you use on your mobile device to help us determine your interests, such as “sports lover” or “outdoor enthusiast.” We make efforts to eliminate the use of websites that may be sensitive in nature.
Custom Experience Plus also uses:
• Device location information we obtain from the Verizon network and from Verizon apps you have permitted to collect location for these purposes;
• Customer Proprietary Network Information (CPNI), including information about the phone numbers you call or that call you and the times you receive these calls. It also includes information about the quantity, type, destination, location, and amount of use of your Verizon telecommunications and interconnected voice over internet protocol (VoIP) services and related billing information.
and this gem:
Q. If I turn off the location settings on my mobile device, will my location information still be used for Custom Experience Plus?
A. We use location information from our network. We will continue to use this type of location information regardless of your device location services setting.