The top U.S. smartphone operating systems by market share

Counting down February 2009's top smartphone operating systems based on current device ownership. The list is derived from a February survey of 39,428 U.S. mobile subscribers over the age of 13, asking respondents what type of phone they own and deriving operating system information based on those responses. The numbers represent current phone ownership at a specific point in time, rather than the total number of devices sold with a particular operating system. Special Report