China's top 10 companies

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With half a billion customers and control of 70% of the wireless market, China Mobile is the country's dominant provider. And unlike the U.S. wireless market, where 9 of 10 consumers already have a cell phone plan, China is only 50% penetrated, leaving plenty of growth left for the cell phone company

But competition is heating up. Profits declined in the latest quarter for the first time in a decade, according to Bloomberg data, as China Mobile waged price wars with high-speed mobile newcomers China Telecom and China Unicom.

Expect China Mobile to continue growing as it expands service to rural areas. Its low-cost plans and phones could attract many of the countryside's 800 million residents.

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