It sometimes happens that someone in public asks for my phone to make a call. I don’t mind in general but I’m a bit worried that someone might call abroad or an expensive premium number. It could even be a planned fraud.
It would be great if I could allow only national calls for guest accounts or, even better, whitelist numbers by the first digits.
Otherwise the “guest mode” does not make much sense to me. The most common reason to share a phone is to let someone make a phone call, and without controlling the expenses this might end in an unpleasant surprise.