Did you know there are more mobile devices in the United States than people to use them? That would be 323 million wireless connections for only 313 million people (that's men, women, children, infants, and maybe even a household pet or two). That works out to a penetration rate of 102.4%, according to the International Association for the Wireless Telecommunications Industry. Five years ago that rate was only 72.5%.

What does that mean for investors? First of all, it's hard to see high revenue growth rates for any major American telecom without it acquiring a competitor. As clearly evidenced by the failure last year of AT&T's (NYSE: T) proposed acquisition of T-Mobile, the threat of antitrust action by the Federal Communications Commission and the Department of Justice makes that a very bumpy road to take -- if not impassable altogether.

Incremental growth can be gained by luring customers away from rivals and by selling existing customers newer equipment that takes advantage of faster networks, which can, in turn, lead to more expensive data plans. But that's an inch at a time.

Three from column B
There is a country out there with almost four times the population of the U.S., in addition to a wireless penetration rate estimated to be only at 74% by the time its billionth cellphone customer puts device to ear sometime this May. That country is China, and its three major telecoms seem to offer investors better growth opportunities than their American equivalents.

No. 1
First among giants is China Mobile (NYSE: CHL). Its subscriber base of well over 630 million gives the carrier huge economies of scale, allowing it to spend as needed on new technology, products, and services. China Mobile also has the highest telecom brand recognition, and since there is no telephone number portability yet in China, there is very little churn.

China Mobile owns 70% of the 2G market but only a 43% share of the more profitable 3G marketplace. That weakness comes about through its use of TD-SCDMA technology, the homegrown Chinese 3G standard. It does not supply the speed available from the WCDMA 3G standard used by its two competitors, nor does it offer much of a selection of handsets.

China Mobile's return on invested capital is a mouthwatering 20.35 for the trailing 12 months, and has averaged 22.26 from 2006 through 2010. It also offers a current dividend yield of 3.5%, which is nothing to dismiss, but it's still a bit less than AT&T and Verizon (NYSE: VZ).

No. 2
Hong Kong-based China Unicom (NYSE: CHU) is China's second largest telecom. Unlike China Mobile, which is a mobile carrier only, China Unicom gets just half of its revenue from providing mobile services. It also offers fixed-line voice and broadband Internet access. Broadband access in China is only 9%, so there is plenty of room to grow.

China Unicom has been aggressively going after the more affluent urban markets, which can afford the higher initial costs and data rates of its 3G service. The carrier has not gone after the larger but poorer rural market, leaving that to China Mobile.

It also was the first Chinese telecom to offer the iPhone. China Unicom may have only a third of the subscribers that China Mobile has, but its 203 million number is still twice the amount of either of the two largest U.S. mobile carriers. It has a projected dividend yield of 0.60%.

No. 3
China Telecom (NYSE: CHA), though much smaller that its Chinese competitors, still has 129 million subscribers -- almost 30% more than either Verizon or AT&T. Like China Unicom, this carrier also offers fixed-line services, and in China's southern region has the market virtually sewn-up. Like elsewhere in the world, fixed-line voice service is dying in favor of wireless, but broadband access is about 30% of the company's business, and there is plenty of broadband penetration headroom.

On the wireless side, like China Unicom, it has also focused on the heavier 3G data-using urban market, choosing not to get into a dogfight with China Mobile for their rural customers. Unfortunately, this telecom lacks the economies of scale that the others can bring, and its weaker brand puts it into a more vulnerable position. However, China Telecom just took iPhone exclusivity away from China Unicom. On March 9, China Telecom began offering the iPhone 4S. Its projected dividend yield is 1.7%.

China Mobile is now the only Chinese telecom without the iconic gotta-have smartphone. But that may not be for long. A barrier to it getting the iPhone has been its desire to have the phone for its 4G LTE network. But with Apple's newest LTE-capable iPad introduced, can an LTE-capable iPhone be far behind? Of course, there will still be issues of which flavor of LTE Apple might use for the eventual LTE iPhone -- FD or TD -- but with China Mobile's enormous subscriber base beckoning, I'm sure something could be worked out.

Growth opportunity in China's telecoms is knocking on the door. Whether to answer it is worth considering.

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