• by Mark Walsh  @markfwal, April 16, 2010

Move over mobile phones. Connected devices like the iPod, Sony PSP, Nintendo DS, and iPad, accounted for 21% of U.S. impressions on mobile ad network Millennial Media in March. Smartphones generated 45%, and feature phones, 34%. In its first week, iPad impressions alone increased 713% in the Apple tablet’s first week in release.

Apple devices overall generated the largest share of impressions on the network, at 40%, according to Millennial’s latest metrics report.

Looking at mobile operating systems, Google’s Android platform continued to gain ground, with ad requests increasing 72%. BlackBerry-maker Research in Motion saw ad requests grow 25% last month. The iPhone OS again had by far the largest share of smartphone impressions, with 70%.

Millennial plans to break out stats for connected devices each month in a separate new Mobile Mix report and plans to include a full analysis of the iPad’s impact on the mobile ad market next month.