Q: The iPhone 5 uses Cellular Data over WiFi?

I'm not sure here, but I think notifications go over the cellular side channel (the same channel used for SMS). A notification contains no data, just a signal to wake a specific app. And apparently turn on WiFi.

DDisable cell data and try this again with the phone asleep.

OK, I just did. Cellular data off. Phone to Sleep. After 30 seconds ping response stops. Activate Find my iPhone using iCloud.com. WiFi comes on and stays on for 2 minutes, then goes off.

AAnd if you send a calendar alert through it should not work.

deggie wrote:

 

AAnd if you send a calendar alert through it should not work.

Sorry, calendar alert also woke WiFi (cellular data still off) for 25 seconds.

All the tests I have run today are with cell-data turned off.

As I move the sleeping iPhone back and forth out of wifi range Find My iPhone detects that.

I tested syncing iTunes with a sleeping iPhone.

I let the phone sleep for 5 minutes.

Battery = 14%, cell-data off, all apps closed, no charging cable, no cable connection to PC

The iPhone does not respond to a ping

In iTunes running on a Windows 7 PC:

I right click on the iPhone under "Devices" and select Sync.

iTunes displays "Looking for iPhone" in a dialog box.

iTunes displays "Syncing" for the sleeping iPhone.

iTunes completes 5 steps of syncing.

The sleeping iPhone does not wake up.

On the sleeping iPhone:

Settings, General, iTunes WiFi Sync

confirm time of last sync on sleeping iPhone

What is interesting about this test compared to others is that the sleeping iPhone does not wake-up even though it is being synced.

I performed another test.

I let the phone sleep for 5 minutes.

Battery = 22%, cell-data off, all apps closed, no charging cable, no cable connection to PC

The iPhone does not respond to a ping

I took my iPhone to a Kroger grocery store and joined the Kroger wifi network.

I put the iPhone to sleep.

When I returned home 30 minutes later, I parked 150 feet from my house to stay out of range of my home's wifi.

Find My iPhone could not find my sleeping iPhone.

I returned the sleeping iPhone to my house and now Find My iPhone can find my sleeping phone.

The sleeping iPhone does not respond to a ping

2 hours later the iPhone is still sleeping.

The iPhone just chimed that it has received an email.

The iPhone does not respond to a ping

Having same problem with my 4s. Left my phone downloading the IOS 8.0.2 update. I have Wifi and phone was plugged in. Data usage 8.7mb showing on System Updates usage. And my ATT usage went up by same amount. Could this be an IOS 8 problem? Never noticed this until I installed 8.0.

No reason to let this subject die. I just upgraded to three IPhone 5s and blew through my data in 1 week. After reading many of the posts and spending an hour on chat with Apple, looks like the best solution is to turn data off.

Completely ridiculous IMHO. Hopeful for a more useful solution from Apple in the near future. Maybe less than two years.

Unbelievable this thread has gone this long with no reasonable solution from Apple.

Thanks alot.

knight1994,

Yes I can empathize.

iOS Settings, Cellular can show how much cell data each app is using.  Unfortunately it doesn't show when and where it was used.

Free apps lihe DataWiz can show when and where you used cell data, but not which apps.

iOS apps are not allowed to show cell data usage by app.  DataWiz did it for a while, but Apple made them stop.

DataWiz also provides warning messages which are helpful.

I was hoping iOS 8 would provide better cell data usage control - but, that didn't happen.  There are some pretty nifty Android apps my friends have showed me.  Hopefully Apple will catch a hint.

I have been having a similar issue since I added 2 new iPhone 5Ss on my plan. Prior to this, they were iPhone 4s. I noticed an extremely high use of data in the first 2 weeks of using the 5Ss. So I started monitoring the situation. I focused more on one of the phones because that phone rarely left the house over the 2 week period. The 2 apps were Skype and YouTube. After finding that, I reset the statistics in Settings->Cellular. Shortly after, I noticed a huge spike of data that was used, 800mb, all at once. I checked on the phone, and sure enough it registered that YouTube used 800mb worth of data. He told me he had recently watched a bunch of videos on YouTube. But the data usage didn't make sense because the phone was connected to wifi. The phone never left the house.

So I then had him shutoff Cellular data for YouTube in Settings->Cellular. Today, he informed me that we was watching a video (on wifi) on YouTube and in the middle of it, he got a message that said "Cellular Data is Turned Off for YouTube". He tapped OK, and it went back to the video.

So my theory is this. If someone is watching a video on YouTube, and the wifi is briefly lost, and switched over to Cellular, then it STAYS on cellular even if wifi comes back. I'm no expert on wifi, but I would expect that it isn't supposed to work this way. But I do think this is the reason why I had such high data usage rates for the last 2 weeks. Thoughts?

ravins515,

I had a similar situation with Facebook a year or 2 ago.  Facebook had put logic in its iPhone app such that it would do some things when it was on wifi and other things when it was on cellular.  The idea was for the app to be smart enough not to use a lot of bandwidth when on cellular.  Facebook had a few problems when they were rolling out the new app and I saw a few situations where it would not detect that the iPhone had moved from wifi to cellular.

My purpose for making this comment is that I am wondering if the majority of complaining in this thread was caused by what I have described above.

ravins515,

I apologize... I took your question as being rhetorical.

I can only give my opinion based on being familiar with this thread.  I haven't actually compiled any statistics on it.

I think when this thread was first started, the cause of the problems being discussed were caused in this order of frequency:

1.  iPhone user unfamiliar with how the smart phone and or their cell network provider functioned.

2.  Faulty apps that used cell data when wifi was available.

3. iOS glitches which caused more cell data to be used than was necessary when wifi was available

4. Wifi going off-line unexpectedly

5. Billing system glitches where the cell network was billing for ghost usage.

Today I think the cause of unexpected cell data usage is primarily in this order:

1. Wifi off-line unexpectedly.  For example, my AT&T gateway was down for 9.5 hours on Sunday morning.  I wouldn't have noticed if it had come back on line before 7:00AM.

2. iOS losing the wifi connection unexpectedly.  For example, I was at McDonalds this evening.  Every time my iPhone woke up it would point out I had cell data turned off for Photos... even though I was on McDonalds wifi.