Originally Posted by
Mary2e
I keep wifi on and cellular off, but I have 2gig of data, and it's not likely I will come close to using it, since almost everywhere I am has wifi these days, including my office, which has off-network service for guests and employee use on personal devices.
I switch on cellular when I want to get email when in the car. As well, I check email manually.
In Settings/Cellular, scroll down and you can toggle which apps can use cellular data and which can't. So, if you manage that list properly, there's no need to turn off cellular data unless you don't trust it. icloud backups won't normally use cellular data.
-David