A recent study has shown that half of all the adults in the Unites States can now access the Internet using that smartphones or tablets. This number has grown significantly in the last few years as a result of heavy mobile device adoption.
Tablets are huge contributor to this growth with 22% of adults now owning one, a number which has nearly doubled since last year.
Smartphone usage has also increased since last year with 44% of adults now own a smartphone, compared to the 35% from May 2011.
source - Pew Research Center