In 2005 the U.S. smartphone penetration of the mobile phone market was a mere 2%. 10 years later in 2015, penetration has now hit 79%, and is still growing, but is finally starting to show signs of slowing down as the market nears saturation.

According to data from a recent comScore report, over the last three years about a quarter of mobile phone owners switched from standard "feature" phones to smartphones. However, like the overall mobile penetration figures, this trend appears to be slowing as well.

comScore found growth in smartphone penetration across every age demographic. Millennials make up the largest age group of smartphone users with a smartphone penetration of 94%, up from 90% one year earlier. On the other hand, the 55+ age group, appears to only have increased a single percentage point to 58% which "may indicate a slow climb to attaining those higher levels of penetration."

Smartphones since the iPhone have had the most disruptive influence on consumer behavior since the arrival of the internet itself. And while hardware upgrades in North America are now largely about platform “switchers,” near ubiquitous smartphone ownership among key groups (e.g., Millennials) translates into mobile-first search and discovery behaviors, which have dramatic impacts on local commerce and advertising — not to mention measurement and attribution implications.