This article has been adapted from  Fool U.K. , our sister site across the pond.

Vodafone (NYSE: VOD) -- the world's largest mobile operator by revenue -- today unveiled its final results for the year to March 31, 2011.

Vodafone's vast revenues
Founded by Racal Electronics in 1982 and demerged in 1991, Vodafone has grown -- in less than 30 years -- to become one of the world's largest companies. Today, the FTSE 100 firm has around 360 million customers in 70 countries, including 19 million in the U.K.

With such a huge customer base, the U.K.-based firm's revenues are vast. In 2010/11, they neared 46 billion pounds, more than 3% ahead of the previous year.

As a result, adjusted operating profit rose 3% to 11.8 billion pounds, at the top of Vodafone's guidance. This included 4.6 billion pounds from Vodafone's share of profits from U.S.-based Verizon Wireless (NYSE: VZ), of which the U.K. firm owns 45%.

Overall, Vodafone's pre-tax profits rose 9.5% to 9.5 billion pounds. Net debt fell by a tenth to just short of 30 billion pounds, leaving Vodafone with modest gearing of 35% of its market capitalization.

Vodafone generated adjusted earnings per share of 16.75p, 4% ahead of last year, with a mighty free cash flow of 7 billion pounds. The final dividend is up 7%.

Vodafone in a two-speed world
As a global Goliath, Vodafone's results show very clearly the growing divide in the world economy. In the words of CEO Vittorio Colao, "Markets remain competitive and the economic environment, particularly across southern Europe, is challenging."

In old-world Europe, which is struggling with sluggish growth and spending squeezes, Vodafone's revenues actually dropped 3.4% to 30.1 billion pounds.

However, in the go-go developing nations of Africa, the Middle East, and Asia Pacific, revenues surged by a fifth to 12.3 billion pounds.

What's more, weak European economies hurt Vodafone even more, thanks to impairment charges of 6.15 billion pounds. These relate primarily to the group's businesses in the ailing PIIGS economies of Portugal, Ireland, Italy, Greece, and Spain. Spain alone accounted for 2.95 billion pounds (nearly half) of total writedowns.

Vodafone gets Smart
In other news, Vodafone plans to launch its own smartphone early this summer. 

A replacement for the Vodafone 845, the Vodafone 858 Smart is an Android 2.2 Froyo OS-based handset which will cost around 80 pounds on a pay-as-you-go tariff. With no contract and a low base cost, and weighing just 100 grams, it is bound to sell well, particularly to first-time smartphone users.

This launch should help to boost Vodafone's growing revenues from data. Thanks to the growing popularity of smartphones and tablet computers such as Apple's iPad, revenues from data rose by more than quarter (26%) to exceed 5 billion pounds in 2010/11. In other words, 1 in every 9 pounds of Vodafone's revenues comes from data, with this proportion sure to increase.

Vodafone value?
As I write, Vodafone shares are up around 2%, valuing the telecoms titan at over $140 billion.

At this price, Vodafone shares trade on a low price-to-earnings multiple and offer a good yield. What's more, the telecom giant has committed to a share buyback program that will reduce its share base by nearly 8%, boosting future EPS.

To me, these are very undemanding fundamentals for a global leader in a fast-growing field, which is why Vodafone remains firmly on my buy list.

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