Hahahah oh man my thought of what funny stuff those sorts might lead to mostly centered around kids at school getting in trouble, but this is way, way better. :)
On the darker side of things I was also concerned about people in abusive situations with hidden phones getting outed, which probably also happened. :(
(I am not a bright guy so I can't take credit for coming up with that on my own, I saw someone post about it on Mastodon.)