Yes, playing iphone is bad for eyes, especially terrible for kids' eyes.
The side effects of playing iphone may include :
1. When your crystalline lenses are exposed to radiant heat produced by iphone, your eyes are more likely to form more blurred image.
2. Microwave radiation from iphone also make your crytalline lenses produce bubbles inside themselves. The bubbles are the omen of cataract and permanent eye damage.
3. If you look at the screen too closely, on the long run, you may develop myopia, dry eyes sydrome, keratitis, and so on.
The situation gets worse when it comes to kids, as kids are still growing up and their physical conditions are not well developed yet.