Source: Asymco

The indefatigable Horace Dediu points out on Asymco.com that although Apple’s AAPL iOS and Google’s GOOG Android are less than two years old as platforms, together they have captured 50.2% of what he calls “the most competitive market technology market on the planet.”

Below: The same data graphed as market share.



Source: Asymco

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[Follow Philip Elmer-DeWitt on Twitter @philiped]