37% of American teens have a smartphone; 23% have a tablet

"Smartphone adoption among American teens has increased substantially and mobile access to the internet is pervasive. One in four teens are “cell-mostly” internet users, who say they mostly go online using their phone and not using some other device such as a desktop or laptop computer.
These are among the new findings from a nationally representative Pew Research Center survey that explored technology use among 802 youth ages 12-17 and their parents. Key findings include:
78% of teens now have a cell phone, and almost half (47%) of them own smartphones. That translates into 37% of all teens who have smartphones, up from just 23% in 2011.
23% of teens have a tablet computer, a level comparable to the general adult population.
95% of teens use the internet.
93% of teens have a computer or have access to one at home. Seven in ten (71%) teens with home computer access say the laptop or desktop they use most often is one they share with other family members."

Source:  Teens & Technology 2013 by Pew Internet & American Life Project, 13th March 2013