Telephony The 2018 Pew Internet Teens, Social Media and Technology report noted that teens use their phone the most of all technologies. 98% of teens have access to a smartphone and the numbers are consistent across demographics including sex, race/ethnicity, income and education.
All that screen time can be a problem in an education setting as research shows the devices are distracting to fellow students and users are not good a multitasking (even if they think they are!).
France is doing something about this problem. In July, 2018 a law was passed banning smartphones and tablets at schools for students under 16.