From comScore:
RIM was the leading mobile smartphone operating system in the U.S. in December 2009 with 41.6 percent share of U.S. smartphone devices. Apple ranked second with 25.3 percent share (up 1.2 percentage points), followed by Microsoft with 18.0 percent share, Palm with 6.1 percent share, and Google with 5.2 percent share (up 2.7 percentage points).
Top Smartphone Platforms
If trends continue on their present trajectory, Google will soon become the fourth most popular smartphone platform in the U.S displacing Palm.
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