How have I used all my data allowance after software update?

[Anonymous]

Since updating software to 9.0.1 - I get a text yesterday at 03.26 (thanks for that!) to say I've used 80% and today at 08.44 to say 100% used? Not by me, so what's happening?

[Cleoriff]

Hi @Anonymous This appears to have happened to other O2 customers who have recently updated. Have a look at this thread here...the post by @Anonymous seems to indicate this has been an ongoing problem (and linked to O2?) https://community.o2.co.uk/t5/Apple-iOS-Devices-iPhone-iPad/internet-usage/m-p/914917/highlight/true#M140130

You really need to contact Customer services and ask them to check it out http://www.o2.co.uk/contactus

[Anonymous · Accepted solution]

Yep, updating to iOS 9 automatically enabled WiFi Assist which uses data even when connected to WiFi. You can disable this by going ito SETTINGS then MOBILE

[jonsie]

It's an o2 issue 100%. So many people have this problem, o2 investigate and yet nothing is ever done.

[Anonymous]

It's 100% an Apple issue.

There are loads of articles about it, this one explains it clearly:

http://www.macworld.com/article/2987233/smartphones/how-to-turn-off-ios-9s-wi-fi-assist-to-save-your...

In summary:

In iOS 9, there’s a new feature called Wi-Fi assist.

When you’re using a bad Wi-Fi connection, it switches over to cellular data. (Typically, your phone switches over to a cellular connection when Wi-Fi becomes unavailable. With Wi-Fi Assist, it kick in when Wi-Fi meets what it deems as a “poor” connection.) 

This is switched on as default.  Turn it off to resolve the issue.

[MI5]

It's been happening on O2 way before iOS9 was even thought of by Apple.

[PhoneChanger]

I think iOS9 has just brought it back into the limelight and has probably exacerbated the issue

[Anonymous]

I've had this too, despite having always had wi-fi assist turned off.

I beta tested iOs 9 and wi-fi assist was one of the first things I checked to ensure it was turned off with each and every beta build.

Moreover I've just checked previous usage on o2 and have NEVER used anywhere near my monthly allowance.

So definitely needs investigating by o2.

[jonsie]

It's down to O2. People changing network find the issue gone. Do a search on here for high iphone data use and you find threads going back years.