Does anyone know how one can make sure the phone uses local wifi connection rather than eats up data from provider when in an area it is connected to wifi. Sorry, I realise this is a basic question but cannot find anything about it on the support pages and was not sent any manual with my new phone.
If you have a working internet connection via WiFi it is automatically used instead of mobile data. So whenever you see the white WiFi symbol with at least one bar in the notification bar you know your mobile data is not touched.
If the WiFi connection breaks though you’ll automatically fall back to mobile data. There are only two things you can do about that: Manually turn off mobile data or set apps not to automatically update in the background via mobile data (many apps have this function).