iPhone X EXCESSIVE data usage

Thanks for setting the scene better. In general the figures in cellular data should be accurate. I'm going to go out on a limb here, and propose a way they may not be - retransmission when a connection is weak. Based on my knowledge of digital communications (which is pretty extensive). An app sends data, or receives data. If everything works, I send 1000 bytes, the the communications channel adds some overhead and sends 1000 bytes. The overhead includes integrity checks ('checksums", but not really) that verify that the transmission was received correctly. If the checks fail the packet is re-sent, and repeated until it is received correctly. It's possible, even likely, that the function in iOS that records the data used by the app only knows about the 1000 bytes, not the retransmissions. But the carrier still records the retransmissions as data (remember that the carrier doesn't know anything about the contents of the packets). So my 1000 bytes will be displayed in Settings/Cellular as 1000 bytes, but if it was retransmitted twice the carrier will "charge" for 3000 bytes. This is just speculation, but it could explain why the data usage reported by the carrier (and charged for) is higher than what the phone displays.

Regarding Wi-Fi, if Voice over Wi-Fi is enabled the carrier actually records that Wi-Fi usage and reports it on your bill as usage. It's one reason that most carriers have gone to unlimited talk (the other is that more people text than talk these days). However, If I call a friend in Paris from New York I get charged for an International call, even though it went over Wi-Fi. Not hypothetical; I DO call friends in Paris from NY and see the charges on my bill.

However, backups do not use cellular data - ever. Voicemail does; it can't use Wi-Fi. Likewise for some notifications and for MMS. Anything that goes through the carrier must use cellular data, because the carrier's system doesn't know how to address your Wi-Fi channel.

What you should do is go to Settings/cellular (it may be called something different in your language) and see which apps and system services are using data. As a check on retransmission, at the start of your next billing period go to Settings/cellular, scroll to the bottom an tap Reset Statistics. After you have done this the total data usage reported on the phone should match the usage reported by your service provider (approximately). There will be a small difference due to overhead.

If if there is a large discrepancy call your provider and complain And follow the advice from Philly_Phan.

Eric,

Here’s one of the discussion pages regarding this cell data issue in case you want to get up to speed on this.

https://discussions.apple.com/thread/8191005?answerId=32685518022#32685518022

Richard C.

Mobile: ***

Home: ***

Sent from mobile device.

I have a supervisor at Apple looking at this. I’ll let you know what we discover. At this point, he had me turn off cell data. Wednesday he’ll call back to analyze any cell data use. Shouldn’t be any. He hadn’t heard of the issue. AT&T said to call Apple. They had no idea why this sudden change to heavy cell data use with the iPhone X if switches were off and WiFi environment stable. They both mentioned that with the new X screen resolution cell data is going to increase substantially, so be careful if you are out, away from WiFi, and your cell data plan is limited.

Bam. Yeah I am suffering the same thing, the first morning I set the phone up I was connected to WiFi and backed up my phone whilst connected to my laptop, it finished up date I unplugged my phone and went to work, once at work as you do I looked at my new iPhone, not much longer I received a text to say I only had 1000 mb of data remaining out of 28gb. I checked my app and it was true all gone. I have been with Apple for 10 years and never have I gone above 10gb PCM. Only the other day I has 1.4gb remaining came home and checked some time later only to find out I was back to a big fat 0 of data left, it’s getting a joke, turn this and that off, what’s the point in having a £1150 phone that I have to switch stuff on and off all the time, I am waiting on a call back from Apple to see what they say, failing that I will be taking the phone back to my service provider and telling them to stick it where the 🌝 dont shine. Hope this helps somebody else who has same issue.??.

I got the X a month ago and just discovered today that I've burned through 1.8G in 3 weeks. I'm in WiFi almost constantly and rarely use the phone out. My normal use is 200Mb per month. I have yet to figure out what is going on with this X gobbling up cell data while I'm in Wifi. Neither ATT nor Apple seems to be able to figure it out.

There was no packet switching when the 3270 was popular! On the other hand, I don't think that it really matters whether it's private line or packet - in both cases, it's a transmission protocol that's intended to reduce undetected errors to a minimum. I think you'll agree that 100% error-free transmission is not possible.

Your explanation makes a lot of sense. Unfortunately, each app is given individual control over message retransmission and conceivably they could all make different decisions, not unlike the humans at the 3270 consoles.

Hi! Juan from Argentina here, this is my first post. I´m having the same issues as described before, excesive data usage on my iphone X. This is my first iphone ever, i come from Android, and i never had issues before with my 5gb carrier plan. I read all this retransmission thread and i sincerely got lost along the way (not much of a tecchie). In simple words, what do i have to do to solve my problem?? Thanks in advance

IF that is the cause of the problem, then don't use data when your cell signal is poor. To oversimplify, the problem is comparable to listening to someone speak in a noisy environment and you continually ask for a repeat.

Is there a special reason why you have set:

Settings > Cellular > Cellular Data Options = "Roaming On"?

I have used iPhones for many years, and have never done that anywhere within the U.S. I suggest turning it to "Roaming Off" - unless you happen to travel internationally frequently and are fully aware of the consequences of your action.

https://support.apple.com/en-us/HT201643

Yes, please report back how you did with cellular use during your trip.

Here's one other thought - from the "Get Help" section of this article:

Check the cellular data usage on your iPhone and iPad - Apple Support

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