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The use of smartphones for children under the age of 20 will damage PFC brain parts (preFrontalCortecs). Indeed today, smartphones like BlackBerry, Samsung, Apple have indeed become elementary school kids toys. In fact, the impact is very fatal for children regarding this brain damage, just as it is now easy to access pornographic content using a smartphone. Actually the forebrain in children is not well developed and the forebrain will mature at the age of 25 years. The front brain is the center that commands the body to do something. While children are not yet time to see negative things and when it is infected it will be difficult to get rid of it.