Mysterious nightly Data Usage charges ?

Yeah... that was a lot of futile effort. There is no 'Apple Facebook page'.

Still, you might want to turn off a few things such as location services and notifications. There's one particular item that keeps running on people's phones, it's the time zone detection, which you can turn off anytime you want in your iPhone settings menu.

An alternative would be turning on Airplane Mode while leaving WiFi on, if you need to stay connected. Or just the Airplane mode. This will prevent any unwanted data transfer overnight.

I don't have an answer from AT&T or Apple, but I have a resolution that requires Apple Developers to implement, and that is simply to check first for Home Network or Primary Network first and if present use that method instead of 3G or 4G to transmit data. However, this requires Apple to implement these changes into their iOS, why they don't do this now instead of later I don't understand. I talked extensively with AT&T technical support and they tried to tell me that this might impact users who are not home, and I simply told them that would not hurt them at all if the system just checked if not at Primary Network to simply use the 3G or 4G, it just adds one layer of check point first before selecting the method of transmitting the data and this would be welcomed by users greatly but means less revenue for AT&T.....

Hmmmm do you think AT&T would even want that??? No reason for them to push this to Apple, it requires the Apple user base to push this change in the iOS, under the network section just be able to lable one network as your primary and to check for that one's presence before sending data.

For Apple this might mean more battery usage which means poorer battery performance, so there might be a trade off, but if you have your phone at night, at home, plugged into your iHome or via Power charging then this alone would save millions of us data usage that is unexplainable from Apple or AT&T but is ever increasing with each iOS update we get.

To answer some of your questions, which ARE answered in the other thread you posted to if you can slog through thousands of messages, WiFi is turned off when the phone goes to sleep to conserve battery, unless the phone is connected to power. If it weren't the battery would run down in a few hours. WiFi requires a continuous data connection at a steady 30 mw drain whether data are being transferred or not, compared to cellular data, which only uses power when sending.

As to why more usage, more apps use more data. And apps can run in background when the phone is asleep. News apps do, for example. As does Facebook. Many free apps are free because they collect data from your phone and "phone home" with it so they can resell it. I saw an article on this a couple of weeks ago, which, unfortunately, I can find right now.

And finally, if you see data charges on your bill with late night time stamps that does NOT necessarily mean data were transferred at the time of the time stamp. That is the time accumulated data usage is posted to the billing system. To find out when the data transfers actually occur you need a monitoring app such as Dataman.

Is your phone plugged in when you think it is on WiFi? If the phone is on standby it will use 3G for data from background apps even if you are within range of a WiFi hotspot if the phone is not connected to power. Dataman can tell you if it was really overnight, and not some other time during the day and just reported overnight.

Dataman Pro just issued an update which shows which apps were using data. Unfortunately, it is only by hour, and does not show how much data each app used. I'm not convinced its accurate yet, but there is something really strange going on. I leave my phone plugged in at night, connected to wifi, and all apps except Dataman Pro closed. I've noticed that every hour, there is a very small amount of cellular data used. It ranges from .5KB to around 17KB. With the Dataman update, I saw that the app sending the data is PHONE. Well, of course, that app is closed. My guess is that the phone is maintaining a cellular link, though why it needs to is beyond me.

This is outrageous. I've been warned of being a top 5% data user and had my data speed throlled down in Feb, so I started monitoring my usage but three days into my new billing cycle ATT thinks I've used 760MB already.

Two of the biggest chunks came from the phantom 3G data recorded around 2AM for 200MB and 10PM for 350MB, both while under wifi, which pushed me over 600MB second day in my billing cycle.

The only time I actively use 3G (or 4G according to ATT) is during my 35min commute, during which I listen to audio podcasts. I listened to TNT show of Twit network yesterday and the audio file is 17.7MB, however ATT's log shows 125MB of data usage during that time. Even with email push email (with remote image download off) you cannot use 125MB unless you stream videos. This record is corroborated by onavo app which also shows 125MB chunk of audio/video data size.

ATT is claiming that data usage clocked may not be realtime and it shows up with some delay, so it possibily means that those 200 and 350MB phantom data came from something I did last month. If this was true it is completely unfair to users that the usage data is pushed over to the new billing cycle. If it was from last month, it shouldn't be counted into usage of the new billing cycle.

But I seriously doubt it, because My Data Manager app do show that data transaction of 200 and 350 around the mentioned time, so it is not just on ATT's record that it happened but real data transfer happened in the middle of the night with WIFI on. I cannot think of any apps doing a delayed data transaction during idle time and even so not on 3G rather than Wifi, so this truly is phantom data.

Also I don't understand why 18MB audio streaming could become 120MB data transaction, bloating it up almost x6. I used to stream video podcast (with unlimited plan, before throttling) and my total monthly usage was around 3GB at max. But at this rate I'll hit 3GB ceiling in a week just listening to audio and sending receiving phantom data packet.

If ATT is so concerned over saturation of network traffic why wouldn't they go into the bottom of this instead of just looking for way to charge users more?

This is happening with cellular providers all over the world, so I think it's an Apple problem, not AT&T.