After 2 days into my cycle, i registered 75% more data usage with Verizon then the Samsung S6 data usage screen had recorded. Verizon went and verified their total was correct and closed the ticket, surmising the device is using more than it records and referred me to Samsung. So far, we have: 1) Forgot the main wifi connection and restablished. 2) Boo up in Safe Mode, verify all apps are able to run off WiFi only (not sure how that is different than shutting of mobile data). 3) Wipe the cache partition.
Now I am supposed to wait and compare data usage in a few days again. Sounds like guesswork to me. Will let u know if I discover anything.
Also should let everyone the Samsung rep was dismayed and irritated that I could infer both the WiFi and 4G icon arrows would work at the same time... I have a screenshot proving this now, but be ready for that argument if you are trying to work with them.
I've also determined that the Message + application from Verizon, establishes a 4G connection and passes data each time an SMS is sent. (with WiFi connected) This seems likely to be a culprit. Guessing there is sending/sent/received communication going on over mobile data. I have message+ with desktop companion enabled.
I just switched my message app from the verizon message + to the regular message app - hopefully that helps. Yes, I was shocked with my data usage! I was home recovering from surgery and on WIFI the whole 5 days and my data jumped up an enormous amount. This is not ok at all. New phone should not cause these new problems. Thanks for the updates. This is very disappointing!
This post is older but I have the S8 and I couldn't figure out why 4G was still lit up even though I was connected to Wi-Fi ( after the fact it was never on before since yesterday) Well yesterday I turned on caller ID with name and then I went and shut it off just a few minutes ago and it went away... Just shut caller ID with name off