Sure, teach them the dangers but also make it as hard as possible for them to access it.

I think another big issue outside of porn is that when kids grow up with phones they turn into people that are always looking at phones. I have some inlaws kids that have phones, and they are just inherently not interesting and dont engage. I agree that phones are a good tool, but when people are constantly having it in their hand it gives them addiction and makes them not interesting.