DOMINANCE: Google's Android software for mobile devices was running on 75 percent of smartphones shipped in the third quarter.

DISTANT SECOND: Apple's iOS system, used in iPhones, was second with a market share of 15 percent, according to an IDC study. Apple's new iPhone didn't come out until late in the quarter.

SIGNIFICANCE: Google makes its operating system software available to phone makers to use in their devices for free. In doing so, Google wins prime placement for its online services, including search and maps. Apple does not license its iOS system to others.