I will have to get back to this one.
My wife and I are raising a single boy late in our lives. He's six now, I'm 50 and wife is still 39 (+3).
Let them play until they are at least six, school and education will come soon enough, watch what they watch (media) and watch your language, they pick up on everything you hoped they wouldn't.
Mine's had an iPad since he was about three and we helped him learn on it before that, he knows more about it than I do. It's not a lie, if you get a new TV and can't figure out the remote just give it to the kid...
Keep apps age appropriate and use parental controls like a SERE instructor, I have failed miserably and my kid thinks Zombie Gunship and Modern Combat 3 are child's play.
If I succeed, he'll know self-discipline, self-worth, the value of money and life, and how to achieve his desires without causing others to judge him. And if they do, the strength, courage, and knowledge to stand up for himself.
Good luck, it's a work in progress...
ETA: I hope to show him all that I've learned in my life, from all my experiences good and bad, right and wrong. If I succeed at that, he'll be just fine!