Sometimes it is very useful that the mobile, we think, but some may be used in a way that, for example, play or use in class time to make friends from all around the us to lose concentration does not intend to learn.
Sometimes the phone was very helpful as we think, but some people may be used in the wrong way, like play time or study. Make friends around, we do not intend to lose concentration.
Sometimes the cellphone is very useful than we think, but some may be used in such a way that play or use in class time. Make friends around us. Distracted. I never study.