The American Academy of Pediatrics is unequivocal: If your kid is under 2, no screens. For older kids, two hours a day, max. But the AAP doesn’t differentiate between activities; education apps, base-jumping videos, first-person shooters, ebooks, Sesame Street, and The Shining are all thrown into the same bucket. It’s all just screen time.

Trouble is, they’re not all the same. An app that teaches your kid his ABCs isn’t the same as a television cartoon, but the AAP is probably right to be conservative with its advice. “Researchers know almost nothing about the impact of touchscreen technology on young children,” says Heather Kirkorian, an assistant professor of human development and family studies at the University of Wisconsin-Madison who is trying to find some answers. “Our society is running a large-scale experiment with real children in the real world, and we won’t know the impact, if any, for many years to come.”

Comforting! All the more so because keeping kids away from touchscreens these days is harder than keeping them away from candy. The screens have become one of our cultural platforms—the modern agora where we get our music, movies, books, social interactions, games, and even education.