Many phones can send pictures and files to other nearby devices. If sharing is set to 'Everyone', strangers on a bus or in a shop can send things.
Device names can also reveal a child's full name and school to everyone nearby.
Setting sharing to contacts only takes seconds, and renaming the device to something generic takes a few more.
If something arrives from a stranger, decline it and tell a grown-up.
The rule from the episode: sharing on? Contacts only.
The rule: Sharing on? Contacts only.
Phishmael & Friends