I have backpain only with see some children near to us, imagine this position during around 4 or 5 hours, how much is the weight of your head, imagine the pressure to your dorsal spine.
But who is the responsibility of this, of course is from parents, no one is the guilty more than parents.
The technology could teach and learn all things for example a new language, a new skill, and of course how the children can be better person learning all good things from others countries.
But if we do not superviser adequately they can learn problems in the web, for example a guy perverted, or an pedofil guy, or porn problem, all problems are in the web.
And backpain of course a problem with their shoulder, brain, eyes, told me how many time spend your children in a screen without supervision adequately, a thinks a lot of time.
This was the reason I think is necessary to enjoy our children and supervised adequately.
Maybe they feel sad because the screen feels good and their brain could feel nice with this, and if you do not let free time with this, the children could angry with you, but in the future they have been grateful with you I am sure.
The pediatric association say, the adequately age to start to see screen are before 6 age, bit the millionaire and intelligent people said is better do not exposed your children to it, is better for your brain.
Sorry by English mistakes, this is not my native language.