Regarding cellular data

[PatDE]

If I keep Cellular Data on all the time, with roaming off, will I incur a lot of unintended charges? It's the only way I can get voice message notifications, apparently.

[Snn5]

Do you use mobile data instead of wifi when available?

[PatDE]

I use Wifi when I can; want to minimize my cellular data use.

[Snn5 · Accepted solution]

Mobile data is something you should keep on, you pay to use it.  BUT, keeping an eye on the apps that use it and how much is used is a big part of the customer responsibility too.  Just be aware that iPhones tend to revert to Mobile Data when on wifi but left dormant for long periods.