Adfonic released their Global AdMetrics Report that stated that the Android mobile OS is used more and is driving most of the world’s mobile ad impressions. The mobile advertising firm says that in the second quarter of 2012, Android had 46 percent of the ad impressions compared to just 34 percent for iOS.

The report also states that the U.S. saw the biggest adoption of Android in recent months and ad impressions in North America for Android jumped from 46 percent to 63 percent from first quarter to second quarter. Meanwhile, iOS fell during that same period from 42 percent to 30 percent.

Despite this, Adfonic notes that the iPhone accounts for 26.5 percent of all impressions among the various smartphones on Adfonics’ network. Similarly in the tablet space, the iPad sees 54.8 percent of all ad traffic.