Apple outshines Samsung on mobile ad network

The iPad, Samsung Galaxy Tab, and Amazon's Kindle Fire were the top three tablets recorded by Millennial Media and were nestled among the top 20 of all mobile devices. A full 95 percent of all tablet impressions came over Wi-Fi connections.Related storiesApple's iPhone dominates mobile ad impressions in Q1Amazon Kindle Fire lights up mobile ad networkAndroid easily outpaces iOS on mobile ad networkAndroid's lead over iOS hits 2x mark on mobile ad networkFinally, smartphones scored 74 percent of all ad impressions, a healthy rise from the 66 percent found in last year's second quarter. Feature phones continued their downward spiral, accounting for only 7 percent of all impressions, down from 17 percent a year ago.Millennial Media compiles data from its mobile ad platform and records "tens of billions of monthly ad requests," according to the company.