Apple's update to iOS 9 included some new features that are designed to help enhance users' experiences with their iPhones and iPads.

One of these aims to help keep users connected to the Internet could also be extremely costly to those with limited data plans.

The WiFi Assist feature in iOS 9 is supposed to help users stay online when the WiFi signal is weak by switching between WiFi and cellular data until a better connection is found, Business Insider reports.

This feature, according to Apple, lets users "automatically use mobile data when WiFi connectivity is poor." This could be a problem for those who have wireless plans with low amounts of data per month.

Users are reporting dramatic increases in their monthly data usage without changing their web browsing behaviors. Whenever a user is in an area with a weak signal, WiFi Assist could automatically kick in and start using up cellular data. If users exceed their monthly quota for data, they could be charged overage fees.

To avoid these potential overage charges, users are encouraged to turn off WiFi Assist. By turning off WiFi Assist, overages from using too much cellular data will not occur, but weak Internet connections will not be improved.

In order to disable this feature, users will go into their Settings, then click Cellular. At the bottom of the screen, they will see the WiFi Assist feature. They can then disable it.

Apple has made WiFi Assist a default feature that is automatically enabled when using iOS 9. Apple probably did this to make sure that iOS 9 users never have poor Internet experiences on their devices.

Complaints could be coming soon from users that ended up going over their data plans and faced charges.