Apple explains Wi-Fi Assist, the controversial iOS 9 feature

It caused especial concern because Apple activates the feature by default on iOS 9 devices.

The bad news? When your iOS device decides to switch to cellular to keep your apps connected to the Internet, all the data sent or received by your device to and from the Internet will be routed over the cellular network.

The document cites that certain safeguards have been built in around the Wi-Fi Assist feature. The other apps could be Safari, Mail or even Apple Maps.

WiFi Assist only works when you have apps running in the foreground and doesn’t activate with background downloading of content.

Wi-Fi Assist, for instance, doesn’t work with third-party apps that stream video or music or contain downloadable attachments, Apple says.

To shut off Wi-Fi Assist, iOS 9 users must go into the Cellular menu in the Settings app, and scroll all the way to the bottom to find the toggle button.

This means that you will open YouTube for example and will start watching videos, or if you have your own channel, start uploading a new video. But like any other release as well, there are a few features that may not always work to the user’s benefit, depending on how you see it. One of those is the Wi-Fi Assist feature, and Apple has now put up a support page to clarify what it does and does not do.

However, as has been pointed out on more than one occasion, accessibility features are not limited to disabled users, but can also allow non-disabled users to improve how they access and interact with their devices.

Apple said that contrary to belief, Wi-Fi Assist does not automatically switch to cellular data when users are roaming.

The easiest way to prevent paying hundreds of dollars on your phone bill because your data plan did not cover all the bandwidth consumed once Wi-Fi Assist activated is to disable it completely. You also need to install the free Lookmark iOS app and log into your account.

Here are the iPhone 6s settings you should change.