First let me say that I'm not posting this because I agree with everything, though there are some valid points backed by research. But I do want to share the article and let you make your own decisions.
In this piece, pediatric occupational therapist Cris Rowan does a great job laying out 10 arguments on the dangers of handheld devices to children under 12. She cites sources and definitely knows a thing or two about the subject.
Of course, there are other factors. Just because I'm told my 8-year-old shouldn't use an iPad doesn't mean I'm going to take hers away. It has educational games and helps pass the time when we're shopping or waiting in an office. She also reads books on her device, so I much prefer it to TV.
Here's the article I read. Be sure to look at the "Technology Use Guidelines for Children and Youth" chart at the bottom:
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