Cellular data used when disabled!

[macstatic]

I've just received my first smartphone (an 1st generation 2016 SE) which I intend to use more or less in the same way as with my old phone meaning phones calls and text messages. So I read this article on how to reduce cellular data on iPhone, but regardless I'm still getting charged even if I do nothing at all!
Well, that's not entirely accurate as I've noticed that I'm charged every time I put the phone into flight mode and back again. I believe I've turned off everything that has to do with cellular data, but apparently something is still going on in the background. Is this a "feature" of having a smartphone which can't be disabled compared to having an old fashioned cellphone, or are there some hidden options which I need to look into? I'm on iOS 15.4.1.

 

[Apple_Robert]

What is your current cellular plan?

 

[macstatic]

Oops -I forgot to say I'm using a prepaid plan, which is why this matters to me.
I never had this problem with my old phone.

Regardless, it seems the phone does stuff in the background. Is this correct?
Is this just the way it is with a smartphone, but depending on the cellular plan it differs how (and if) they charge for all of that?

 

[Apple_Robert]

Oops -I forgot to say I'm using a prepaid plan, which is why this matters to me.
I never had this problem with my old phone.

Regardless, it seems the phone does stuff in the background. Is this correct?
Is this just the way it is with a smartphone, but depending on the cellular plan it differs how (and if) they charge for all of that?

Make sure you have "background app refresh" turned off, as well as location services. If you have had those two options turned on, that could account for you using cellular data outside of the unlimited talk and text most are allowing for with the prepaid plans.

 

[eyoungren]

I would also turn on WiFi (you can do that while Airplane mode is on). My thought for that would be that perhaps the phone, recognizing that WiFi is on, would use that over cellular.

 

[Mr.Blacky]

Just turn off cellular data. ?‍♂️

 

[macstatic]

Make sure you have "background app refresh" turned off, as well as location services. If you have had those two options turned on, that could account for you using cellular data outside of the unlimited talk and text most are allowing for with the prepaid plans.

I believe I already had that turned off, but checking again I had it set to "wifi" (instead of "Wifi & cellular data" or "off"). I'll turn it completely off just in case...

I would also turn on WiFi (you can do that while Airplane mode is on). My thought for that would be that perhaps the phone, recognizing that WiFi is on, would use that over cellular.

But that would depend on the various apps or services set up to use wifi instead of cellular. I've disabled cellular for all apps and even signed out with my Apple ID, so this shouldn't make any difference, should it?

Just turn off cellular data. ?‍♂️

Yes, cellular data is already turned off, but somehow I'm still getting charged every time I go from flight mode to turning it off (and thereby turning on cellular). I'm checking this by logging into my phone service's web page where I can check how much money is left on my prepaid plan (thereby eliminating any guesswork as if checking this from the phone is the actual cause of it -which should be free anyway as far as I know).

UPDATE: a correction to the above: nothing is charged if I go from cellular turned on to flight mode (cellular off), but as soon as I go into flight mode after having had cellular on I'm charged for some reason. Any ideas what this could be?

 

[now i see it]

Every time that Flight Mode is disabled so that the cellular antenna works, the phone contacts the cell tower and likely sends a bunch of things to Apple and whoever. But the data stream is very small.
I’ve never known of a prepaid plan that charges by the KB. Usually the monthly prepaid plan payment includes a set amount of data usage (1,2 GB).

 

[NoBoMac]

^^^This.

If you look under System Services under Cellular, "Cellular Services", "Find My" probably are exempt from the main "Cellular Data" switch (core-ish services vs user-ville). Ditto "Networking" that might be doing some ping-like function to test the waters as well as "Time & Location".

"Apple ID Services" might be sneaking through as maybe "core".

Interesting black-hole: General. #4 for system's cellular usage in my list.

 

[macstatic]

Having no prior experience with iPhones, but having used iPads for several years I've realized that I've completely misunderstood the "flight mode" setting.
I thought "flight mode" was basically a common switch for turning on/off a variety of communication forms at once: wifi, bluetooth and cellular.
But now I understand that the green circle/antenna icon is for cellular data, while "flight mode" in itself turns off all cellular communications (including cellular data).
In other words: I've turned on/off the green cellular data icon all the time instead of just keeping cellular data off and pressing the orange flight mode button instead, in order to disable phones calls/SMS messages at night etc.

OK, so that should at least clear up things so that I from now on keep cellular data off in general, then for the occasional need for apps that use cellular data I can switch it on.

Yes, there's a small charge each time I go from cellular data off to on (but having figured out the above confusion it appears I'm not charged for simply switching between flight mode on/off. Phew!). You're right that the charge was very small.
However, something else has charged a lot at once. I have no idea what it was -perhaps software update checking or app updating in the background?

Looking through Settings-Cellular-System services I see that there's been a whole lot of traffic. The highest numbers being:

Software updates: 58.3 MB
Security services: 21.2 MB
Messaging services: 7.2 MB
Push notifications: 4.1 MB
Apple ID services: 2.4 MB
iTunes media services: 1.9 MB
iTunes accounts: 1.1 MB
DNS services: 656 KB
General: 467 KB

Can some of these be disabled?
I've disabled software update (Settings-General-Software update: automatic updates: off), but I see that whenever I go to "Software update" it goes online and checks. At least when wifi is on. Will it do the same thing whenever cellular data is on (and wifi is off)? If yes -is there a way to disable this checking if I accidently go to "software update"?

I'm glad I figured out the difference between "cellular data" and "flight mode", but for the couple of apps I need to occasionaly use with cellular data I hope I can figure out how to eliminate all sorts of other things sending/receiving data simultaneously.

 

[mblm85]

Have you got Wi-Fi Assist enabled? It might be that.

 

[macstatic]

Yes, I read about that somewhere, so it's disabled.
Once having sorted out the differences between flight mode and cellular data on/off I've done some further testing today.

I first started off by taking the first screenshots (Settings-Cellular data, then scrolling down to the "Cellular data: current period" section where it shows the total bytes of data transferred, and another screenshot of all the system services by going to Settings-Cellular-System services to see exactly which service transfers how much data. I kept taking these screenshots as I went along to easier notice any changes.

So at zero bytes of data I turned cellular data on, and immediately saw some data being transferred. As far as I remember this is the first screenshot after enabling cellular data:

Then a little later (and still, I'm doing nothing on the phone), more data is transferred and I notice a new item (Mapping services) popping up in the list:

Finally, about 30 minutes after the first screenshot, this is what I'm ending up with:

Obviously a lot of things are going on in the background, but figuring out what is the tricky part.
I've tried these settings as follows:

Settings -SIGN IN TO YOUR PHONE (off)

Settings - General - Software update -AUTOMATIC UPDATES (off)
Settings - General - Background app refresh - BACKGROUND APP REFRESH (off)
Settings - General - Date & time -SET AUTOMATICALLY (off)

Settings - Cellular - WIFI ASSIST (off)
Settings - Cellular - Cellular data options - LOW DATA MODE (off)
Settings - Cellular - Cellular data options - LIMIT IP ADDRESS TRACKING (off)
Settings - Cellular - all apps listed here (off)

Settings - Siri & search (off)


Oh, I've also tried to set "Low data mode" and "Limit IP address tracking" both to ON, but it didn't seem to make any difference. Something I haven't tried yet are the notifications (Settings -Notifications). Do these have something to do with push notifications, or are they just for configuring how things already happening on the phone are to alert the user?

 

[Nermal]

If you look under System Services under Cellular, "Cellular Services", "Find My" probably are exempt from the main "Cellular Data" switch

If that's the case then it should be logged as a bug. The description next to the Mobile Data toggle says "Turn off mobile data to restrict all data to Wi-Fi" (my emphasis).

Interesting that it's called "Cellular" on yours; it used to say that on mine but changed to "Mobile" a few versions ago.

 

[NoBoMac]

Interesting that it's called "Cellular" on yours; it used to say that on mine but changed to "Mobile" a few versions ago.

Probably one of those things that is controlled via carrier settings. Regionalization, if you will, in this case.

 

[macstatic]

Probably one of those things that is controlled via carrier settings. Regionalization, if you will, in this case.

I believe it depends on which language you set up the iPhone for (in Settings-General-Language & region) such as "English (US)" or "English (New Zealand)" and so on.