Hi Yes I did get some updates one of which was Google Play and also Android System WebView Neither of which should necessarily cause the issue with the data. Still fooling around with it. Trying some Router changes based on some other posts however i suspect this is really a Lollipop issue with the hardware.
After doing some research I found that the 4g symbol will stay lite as long as you have 4g service. The arrows below the symbol let's you know if data is being sent or received. If your location setting is set at a high accuracy then you will use both Wi-Fi and data. If messages are being sent or received then data is being used. There are several settings and functions of your phone that require mobile data even if you're connected to Wi-Fi. I wouldn't worry about it unless your seeing a dramatic increase in data usage.
My note 4 is doing the same thing since software updates. i.e. Lollipop update. I have to turn my mobile data off and manually connect to home wifi. My phone use to hook right up immediately as I pulled into my driveway at home. Doesn't do that either. Have to manually connect to home wifi now.
I was on the phone last night first with Verizon, no change. Than with Samsung. Still no fix for this issue. The woman put me on hold to figure out what more to do, 10 minutes on hold she didn't come back. I hung up. I do not trust these companies. Amazing, two weeks into data plan and already used over 2 GB. Never did that before. A plan to get you to purchase more gigs or pay overages? I need a fix or I am not going to accept this for either companies. Their problem, not ours
Settings ! WiFi. Then click menu and Advanced WiFi. What do you have selected?
Its possible, even with SmartSwitch disabled, I think that's it, the behavior of the device is incorrect and may remain so, unless you backup personal files, write down critical settings like for email, get usernames and passwords ready, and perform a Factory Data Reset, and start over.
Have the Galaxy S6, 2 weeks now. I have been monitoring this situation closely on my phone prior to reading all these comments. While generally both lights are on continuously and see data being passed on both 4g and WiFi, I have caught both YouTube and Instagram aps actively using the 4g data, and Im now 65% into my plan... more than I use most full months. It would seem it decides when it wants to use 4G instead of wifi (smart switch is off), but generally is not eating up data.
I've been turning off the mobile data icon, to put a halt to it, but totally paranoid everytime I see the arrows now. Needs be fixed please Verizon!