Yes it's true but it's not limited to or even primarily phones. It's disruptive students who cannot sit still or listen to lessons regardless of whether they have a phone or not. Phones are an easy scapegoat for shit parents who won't do anything to set their kids on the right path. Anything wrong their kids do must be because of someone else. Ban the phones all you want. These parents will still be shit parents and their kids will still be disruptive in classes. We cannot tackle anti-social behaviors because it's largely a protected political and religious class.