I have just an ordinary cell phone so I don’t use data, but I have a data plan with Verizon because there’s three other phones on the account that do use it. A Verizon rep told me that users should close out apps after using them because they still use data when the phone isn’t being used. Also, my oldest son had used his “hot spots” option on his phone, and forgot to shut it off. Because of that the phone used extra data that he wasn’t aware of. Verizon also offers a “Safety Mode” app that automatically slows your data speed when you’re getting close to your limit. That’s about all I can offer based on my limited knowledge of data usage.
Thanks everybody. You’ve given me a lot to start with.