I have an iPhone XS. I was told by AT&T support that when I am connected to WiFi on my device that I will continue to use cellular data unless I turn off my cellular data. I am baffled by this. It is my understanding that when you are connected to WiFi that your phone uses the WiFi connection instead of the cellular data. Thanks.
iPhone XS, iOS 12
iPhone can use cellular data when connected to a weak Wi-Fi network.
If you do not want this to happen, disable Wi-Fi Assist under Settings > Mobile Data. Scroll all the way down and disable "Wi-Fi Assist". Here you can also see how much data iPhone used for this.
iPhone can use cellular data when connected to a weak Wi-Fi network.
If you do not want this to happen, disable Wi-Fi Assist under Settings > Mobile Data. Scroll all the way down and disable "Wi-Fi Assist". Here you can also see how much data iPhone used for this.
Using cellular data while connected to wifi
