16-17, 18-19, ADOLESCENT, APPLICATION, BOY, CELLPHONE, CELLULAR, EDUCATION, FACEBOOK, FOUR, GIRL, GROUP, HIGH, HIGHT, INDOOR, INSIDE, MOBILE, NETWORK, OF, PEOPLE, PHANIE, PHONE, RECEIVE, RECEIVING, SCHOOL, SCHOOLING, SENDING, SITTING, SMART, SMARTPHONE, SMARTPHONES, SMS, SOCIAL, STUDENT, TEEN, TEENAGE, TEENAGER, TEENAGERS, TELEPHONE, TWITTER, USING, VOISIN, WRITE, WRITING, YEARS, YOUNG,