Those age 25-34 accounted for the largest segment of the total smartphone audience at 22.3 million users (up 47% from the previous year), followed by those age 35-44 accounting for 17.5 million smartphone subscribers (up 36%).Although representing a small audience base, those in the 55-64 and 65+ age groups experienced the strongest growth in terms of percentage increase. Smartphone owners age 55-64 grew 86% to 6.5 million users in July 2011, while those age 65+ accounted for 4.4 million smartphone users, up 127% from the previous year.Analysis of teen smartphone usage showed that 5.6 million teens (those age 13-17) owned a smartphone in July 2011, up 53% from the previous year.