zlacker

I like this solution, integrated with whatever existing parental controls are in the OS.

That would empower parents to keep their kids from accidentally or casually accessing porn. Of course, an intelligent and determined teenager will probably find a way around it, which is also good; then they've learned a bit about computers.

>>Zak+(OP)
I'm going to bet most kids will get around it by registering accounts with the IDs that they've taken pictures of, which belong to adults, then sharing the accounts widely.

Grandma isn't likely to have an account on one of these sites (unless one of your cousins beat you to it).