This survey analyzed teen smartphone usage by site (e.g., Facebook, Instagram and Snapchat are the most popular social media sites) and demographics. 92% of teens go online daily, and a quarter state that they go online, mainly by phone, “constantly.” African Americans were most likely to have a smartphone; of teens who did not have such a phone, only two-thirds went online daily.
Pew Research Center. (2015). Teens, Social Media & Technology Overview 2015: Smartphones Facilitate Shifts in Communication Landscape for Teens. Washington, DC: Pew Research Center. http://www.pewinternet.org/files/2015/04/PI_TeensandTech_Update2015_0409151.pdf