You shouldn't have to, but if your phone doesn't connect to wifi you may have to force it. The quality of your wifi may make a difference as ypur phone is designed to connect to the best connection possible.
You can change settings to prevent data over cellular.
Open settings
Go to cellular/mobile data
Scroll down to apps used.....
Tap each app that you want to restrict and then scroll down and check "restrict background data"
Social media apps must be restricted within the app itself.
Same with email.
App Store should be restricted to update over wifi only.
You can change settings to prevent data over cellular.
Open settings
Go to cellular/mobile data
Scroll down to apps used.....
Tap each app that you want to restrict and then scroll down and check "restrict background data"
Social media apps must be restricted within the app itself.
Same with email.
App Store should be restricted to update over wifi only.