Once I had got over my deep deep shame at being one of their parents, I would have immediately confiscated their phones until they could prove to me they warranted having it, and I am no pushover.
Resisting the urge to tan their blummin backsides, I then would have considered why they did this at all, sat them down and told them what the emergency services are needed for..in quite an adult and graphic way.
Then, it's volunteering for the whole holidays, doing something useful.
It's a darn sight better than I would have got if I'd have done this.