icloud backup using data over wifi
Hi, over the last 3 months I have noticed that when my iPhone 5S is backing up to the cloud at night, it drops the wifi connection and backs it up using my data so I am using a huge amount of data outside of my monthly billing cycle. Does anyone know if something in the phone can be activated to only using wifi when doing the icloud backup?
Thanks for your help
Carrie
iPhone 5s, iOS 8.4.1