The unlimited data plan is something of a rarity these days, due to high-speed 4G packages meaning we’re downloading and consuming data more than ever. The majority of us on a limited data package will have already spent some time ensuring our settings are tweaked to prevent our iOS devices consuming this monthly data allowance within just a few days.

That could include restricting updates to Wi-Fi, or turning off background refresh. However, a new setting that was automatically activated in iOS 9 could mean data is draining away faster than ever, even if you’re on Wi-Fi.

The setting, which some of you that upgraded to iOS 9 on September 16 may have noticed, is called Wi-Fi Assist. It’s purpose is to support poor Wi-Fi connectivity. While it’s great at avoiding disruption when browsing on a weak Wi-Fi signal, if you’re downloading apps for example, then your cell package could be supporting those downloads. If you’re worried about using up all your data, or you’ve experienced higher than usual data-usage, then it might be worth turning off Wi-Fi Assist.

It’s easy to do, simply head to Settings Cellular and then scroll all the way to the bottom and toggle the Wi-Fi Assist option to off.

wifi-assist

However, if you’re on an unlimited data package, then congratulations! You’ve just gained a great new feature in iOS 9. Happy browsing!

Read more: iOS 9 adoption hits 50% in just five days