Telcos warn about iOS 9's Wi-Fi Assist feature

Phone companies around the world are warning about a new tool added by Apple with its free iOS 9 software upgrade for iPhones and iPads last week – and its potential to blow out your phone bill.

"Wi-Fi Assist" automatically switches your iPhone to a 3G or 4G mobile network connection if wi-fi connectivity is poor.

The problem is that in the US, where Apple probably conceived the new feature, many people are on unlimited mobile data plans, or at least plans that offer a generous amount of mobile data.

But in many countries, including New Zealand, mobile data plans are typically capped, and relatively expensive – so using mobile data to compensate for a lousy wi-fi connection can blow your cap rapidly.

That's already happened to one Kiwi user, who can only be identified as Tony S. 

After buying an iPhone Plus with iOS 9 installed, Tony blew through 3GB in two days.

His 2degrees plan tops out at 2.5G and he has to pay $2 for every 100MB he exceeds after that.

Most people are on plans with 1GB of data or less, so Wi-Fi Assist could land them in a bigger hole.

And unlike equivalent features on some Android and Windows Phone handsets, iOS 9's Wi-Fi Assist is switched on by default.

How to turn it off
Vodafone is among carriers that have alerted customers to the issue, at least in online support forums. Its instructions on how to disable Wi-Fi Assist (here) apply equally to someone using an iOS 9 device on Spark or 2degrees – but you'll probably have "Mobile" or "Mobile" data listed under "Cellular," so hit Settings, Cellular (or Mobile Data), then scroll right down to the bottom where you'll see a slider to turn Wi-Fi Assist on or off.

Wi-Fi Assist does not appear as an option on older iPhones that have been upgraded to iOS 9.

Turn it off by default - Tuanz boss
"In principle Wi-Fi Assist is a great idea to help keep us connected, but in our market where we have data limits on our mobile data plans we all run the risk of unknowingly using up mobile data," Telecommunications Users' Association chief executive Craig Young says.

"I have personally turned it off, and would encourage people that are concerned to do so to.

"My preference would be that it was off by default and then let individuals choose whether to use the feature."

Apple did not immediately respond to NBR's request for comment. Nor did Vodafone NZ or 2degrees. [UPDATE: A spokeswoman for 2degrees says it has just posted an online guide to Wi-Fi Assist.]

Spark declined the opportunity to comment.