Using mobile phones in a public place

Using mobile phones in a public place. Innovation of phone was the great step in Industrial Revolution. But science moved forward. Now we have mobile phones. It is difficult to imagine our life without them. Many people save the to decide their problems just in time. But we mast follow the rules of using mobile phones. First of all, we shouldn't use our mobile phones at the cinema, at the library, at the theatre, at school because we are concerned about talking on our phone and disturbing people near us. Also,children are just wasting money and time on them, and it could damage their health. But on the other hand we think, that we shouldn't switch our mobile phones off, because our parents can need our help and we must go home. Not so long ago people didn't use mobile phones and the life seemed quite well. I worry about our future generation. If it brings damage to young people what we use them for?