iOS 9 mobile Wi-Fi Assist hitting customers with huge data bills

Check your settings before your mobile data costs go through the roof

Apple's iOS 9 mobile operating system is reportedly causing expensive problems for customers, as its "Wi-Fi Assist" function - which supplements poor quality Wi-Fi connections with mobile data - is apparently causing customers to inadvertently bust their usage limits, sending bills spiralling out of control.

As reported by MoneySavingExpert.com, the function, which Apple describes as a feature that will "automatically use mobile data when Wi-Fi connectivity is poor", is seeing some individuals using more than three times the amount of their usual data allowance, as the Wi-Fi Assist function quietly eats away at their data.

One customer quotes having used 6.7GB of data instead of an expected monthly usage of 2GB, before discovering Wi-Fi Assist and turning it off, while another reports having used 7GB instead of the usual 1GB-2GB.

Wi-Fi Assist is switched on by default, but can easily be turned off in the Settings menu in iOS 9. The worry is that not many people even knew it had been introduced in the new operating system or were unaware of the implications.

On the bright side, Wi-Fi Assist doesn't kick in when data roaming is taking place when the device is abroad, so data bills climbing to catastrophic levels should be avoided.

However, it should also be remembered that iPads beyond the iPad 2, as well as the iPad Mini, that contain SIM card slots will also have the Wi-Fi Assist feature ticked by default as well. As far as phones go, the feature only exists on the iPhone 5 and later handsets.

Wi-Fi Assist is proving a controversial feature for iOS 9, with supporters pointing to an increasing prevalence of unlimited mobile data contracts as grounds for considering it a useful feature.

However, Google's Android Marshmallow, which launched only yesterday, is not following the trend - offering a form of supplementary Wi-Fi through mobile data but relegating it to an option a user must activate manually.

Do you have any experience of Wi-Fi Assist on iOS 9, and how is it fitting into your personal or company data allowances? Let us know in the comments below.