Wi-Fi Assist is a nice feature added to iOS 9 and iOS 10. In the event of a poor or weak wireless connection, Wi-Fi Assist, when enabled, automatically switches over to and utilizes your cellular data in order to maintain a stable, continuous Internet connection. Instead of having a webpage load partially due to a weak wireless connection, Wi-Fi Assist utilizes your cellular data to keep the connection smooth and allow the webpage to continue to load.
While Wi-Fi Assist certainly seems nice and generally beneficial, having Wi-Fi Assist enabled can also lead to an increase in utilization of cellular data. For users with small or moderate data plans, this potentially can result in unexpected monthly data overages and hefty data overage charges on your monthly bills. Some carriers charge a minimum of $10 to $15 per additional GB of data.
Wi-Fi Assist is enabled in iOS by default. As such, to disable Wi-Fi Assist, go into “Settings” then “Cellular.” Scroll all the way down the page to “Wi-Fi Assist” and toggle the on/off button to the off position. Wi-Fi Assist is now disabled!
While you may lose the benefit of having a stable, continuous Internet connection in the event of a poor or weak wireless signal, you can sleep a bit better knowing Wi-Fi Assist is not contributing towards your monthly data overages.