According to Millennial Media’s April report, Android is the leading smartphone OS on their network. This is the fifth time in a row that Android has held this position and shows its dominance in the smartphone OS market.
Smartphones are only one part of the mobile devices mix (albeit the dominant part), and the report also points out that impressions on non-phone mobile devices have risen 200% between Q4 2010 and Q1 2011.
Apple iOS devices accounted for 28% of the smartphone mix (iPhone) and 16% of the rest of the mobile device mix (iPads and iPod Touches). Additionally iOS devices accounted for 50% of app revenue in April, compared to Android’s 39%.
The full report is available from the source link. Millennial Media also produced a nice infographic of how the mobile device market breaks down by OS.
Source: Millennial Media — Millennial Media Releases April Mobile Mix Report