The data use can be your device doing a back up which if you have cellular data on will when plugged in the charger revert to cellular if you do not shut it down.
The iphones have a knack of going into sleep mode even if WiFi is available, however when on cellular it uses cellular as default unless you turn cellular data off. I turn mine off prior to placing the charging cable into my device.
Additionally go into apps management and turn them off from using cellular and let them use WiFi.
And make sure your emails don't check for mail automatically but set them to be retrieved when you click on them manually.
Should have other ideas.
This happens to my daughter's phone, too and I am getting ready to trash the phone unless this can be corrected. It is only 21 days into my month and we are on the 6th overage - and I get 6 already! This process used 1.25 G in ONE download of WHAT? I am really thinking about making her go back to her old Android phone. The cost of this is outrageous - I have paid for the phone twice over already.
I'm having the same issue and this month these data pulls equated to 1891.51 MB!!!
Model: iPhone 5S 64GB. Today I received a notification from Verizon that I had exceeded my data plan. I just went through my entire usage detail report on my phone and separated-out everything that appears to be part of a 6-hour pattern. When I'm at home and most of the time while I'm at work, I am connected to wifi. These data pulls often happen in the middle of the night, when I know for a fact that my phone is charging and connected to wifi at home. Below are the results of the pattern analysis. Keep in mind that I removed all lines that, as far as I could tell, were not part of a 6-hour pattern.
THE PROOF: You sent me three alerts immediately after pulling data from my phone.
The first alert said that I had used 75% of my data plan on 8/11/2014 at 9:45pm while I was at home on wifi. There was a data pull logged at 9:45pm which was part of the 6-hour pattern above.
The second alert stated that I had used 90% of my data at 10:46pm on 8/14/2014; the data log shows a pull just before the alert at 10:45pm.
The third alert telling me I had used all of my data came today while my phone was sitting next to me, connected to wifi at the office. The alert arrived at 12:48pm, the log shows a data pull at 12:48pm.
How about an explanation Verizon?
See lindsaypink's reply above... her screeshots capture the problem we're having very well. I did turn cellular off and on and I am still getting data pulls. Elector's theory above didn't pan out. However, he was right if you shut off cellular, it doesn't happen. Any help on this topic that you can give it would be appreciated.
Check this link out to see if it helps.
and this video
This is an obvious problem for MANY users. Some cases more severe than others but none-the-less a problem that continues to be ignored. Every device I have with Verizon (iphone5s, iphone6, galaxy3,and two ipads) are getting random data pulls every 6 hours.
We have turned off background updates, cellular data, wi-fi all the recommendation we can find here and on the hundreds of other site discussing this issue... for the past two years. We even checked the stuck email scenario the reset upon reset and once the device is physically turned back on... every six hours more data is pulled than we ever use during the month across 5 different devices.
Verizon. What is your policy regarding unexplained data use that we can prove we have done everything about to STOP and yet it continues on your network - I'm pretty sure it is your network that is causing it, but I want to know your policy.
And don't brush this off to some lame YouTube hack. Let's see if you actually have a real answer to your policies and solving this issue.
I had this same problem. It only happens on two phones on our plan, both iPhone 5ses. One from Dec 2013, one from Nov 2014. After looking in to it and reading over several posts in different forums, I am pretty sure it is just the amount of data that is used every 6 hours all added together. For iPhones, if you go to Settings, Cellular and then scroll to the very bottom, you can reset your statistics. Then monitor how much data you use for 1 day and what apps are using it. The apps that were using a lot of data for us were: Mail, Safari, Maps, Facebook, Instagram, Twitter, and Snapchat. Every time you load these while you are not on WiFi, it uses a lot of data to download whatever information you want. If you are bored and downloading a lot of pictures or videos (thanks Facebook for autoplaying them all for us and using our data like crazy...) without even realizing it, you could rack up the data pretty fast. Add all of that up in a 6 hour period and it could seem like a very large chunk, especially when it updates the data information while you are asleep. If you want to prevent yourself from using your cellular data for these applications, you should be able to turn them off on that same Settings, Cellular tab. I haven't done this for most of my apps personally because I only need to use Maps while I am driving around without WiFi, but it would help to remind me that I can wait until I get somewhere with WiFi to check out all of my friends on social media. As for the other iPhones on our plan, a 4S and a 6, they don't update the data every 6 hours. The 4S is kind of random so I'm not sure how often that is updated, but I think the 6 is every time you use data. We have pages and pages of data log for the iPhone 6. Anyway, I hope this helps all of you that are going over your data every month. It's not a fraud, but I am disappointed that no one from Verizon has figured this out earlier for all of us iPhone 5s users.