I am sitting in Berlin, writing this article on an iPad.

I just finished reading the biography of Steve Jobs by Walter Isaacson, and it convinced me how radical the change in my grandchildren’s lives is from the life I led growing up.

I’m old school. I learned to memorize multiplication tables, wrote with a pencil on lined paper, carried textbooks to school in my hands, used a typewriter and made changes with Wite-Out, studied with long-playing records on a separate stereo, never used a printer, a fax or a scanner, grew up listening to radio shows, and watched TV on a 16-inch black-and-white set that was the only one in our apartment.

I went to elementary school half a block from my apartment in Brooklyn, came home for a lunch my mother prepared, and played sports, cards and games on my street without parental supervision. We had no coaches and no organized teams, and we made up our rules as we needed them.

I’m in Berlin visiting my grandchildren. While I was sitting on the couch, reading the Steve Jobs hardcover book, my grandson (age 10) was playing games on a cellphone, my granddaughter (age 8) was playing a game on my iPad, and my younger grandson (age 6) was watching a kids’ movie on Netflix.

The world is radically different for our youth today than when I grew up. Cellphones are replacing telephones. I can call people in Atlanta for a few pennies a minute from Berlin or even free on FaceTime and see their faces.

Long-playing records are extinct; even music on a CD is not necessary. My grandchildren can find any song or music on Spotify free in less than minute. I tested them, asking one of them to find “Hotel California” by the Eagles, and I was listening to it before I could say my full name.

Books are being replaced by electronic books. I was reading a 600-page book on the airplane, while the woman next to me was reading a book she had downloaded onto a Kindle. My book was big and bulky, while her Kindle was small and thin. Bookstores are on the way out.

I grew up with movie theaters showing two movies with cartoons between them. I bought several hundred DVD movies, and now they are mostly unnecessary because they are available on demand on Netflix or over the Internet.

My car allows me to dial anyone on my contact list by my voice or by the press of one button, and someday we won’t even need to drive our own cars.

In an urban setting like Atlanta, you might not need a car at all because you’ll be able to rent a car by the minute, park it anywhere near your destination, and let someone else rent the same car a short while later. This is already happening in Berlin.

I can hear my favorite U.S. news show on my computer in Berlin, while my son in Berlin can read The Washington Post in his home. I can read Jerusalem’s Haaretz newspaper in my living room in Atlanta, and I don’t need a siddur to pray anywhere in the world because it is on my cellphone.

There is a real conflict for parents these days. How much time should children be allowed to play games on a computer or a cellphone? My grandchildren, especially the boys, want as much time playing computer games as they can get.

Is learning from a computer better or worse than real textbooks? When should a child be given a cellphone or a computer? What TV shows or movies should be off-limits?

I am glad I am their grandfather and don’t have to make those decisions. I know I am a softy, and they get away with more from me than they do with their parents.

The bottom line: Stay out of raising your grandchildren and leave that to your children. How well they do it reflects how well you did it.