And in case anyone is wondering, her vocabulary soared after we started letting her use the phone, and most people comment on how advanced her language skills are, so anecdotally the phone seems to be helping her not hurting her, despite all the objections we get when they see my toddler using a phone.
But I guess we'll see. Every kid is different, so YMMV.
He's now 5 and uses an iPad now and then, solely to play Scrabble against the computer. His vocab is very good: he can usually beat the computer and has had 400+ point games. The other month, I noticed him playing against himself rather than the computer. He said it was because it meant he got twice as many turns!
But then what? What will happen when they need to spend time with themselves? How will they relate to other people? What happens when novel information is no longer novel? Will drugs help? How will they cope with the stresses of life?
This is a slippery slope. We are only now seeing how total the consequences to what it means to be a social people.
Children are quite robust.
I think the magic ingrediences here is love, hugs, attention (when they seek it) and time is what truly matters. That will guide down the slippery slope they will take regardless. If the kids want to play, learn from it and can let it go without having problem with it, it should ok.
Anyway it's something they need to learn since most things in life will be tied to electronic devices.