If you're wondering how your portfolio can benefit from the craze over the latest ïPhone and 4G networks, Crown Castle International (NYSE: CCI) might be the stock you're looking for.

Crown Castle owns, operates, and leases towers for wireless communications. While it primarily operates in the United States and Canada, it also does business in Australia. Crown Castle provides the infrastructure to enable voice and data services for wireless carrier customers such as Verizon (NYSE: VZ), Sprint (NYSE: S), and AT&T (NYSE: T).

Crown Castle competes in a highly concentrated industry. For the moment, it plays well with primary rivals American Towers (NYSE: AMT) and SBA Communications (Nasdaq: SBAC), thanks to the industry's favorable economic conditions. Rising demand for wireless data services such as Internet and text messaging has fueled significant growth for all three major players.

Crown Castle alone achieved a very nice 10% revenue increase for its latest quarter; over the last four years, its sales have enjoyed compound annual growth of just more than 26%. Future revenue growth should remain similarly remarkable, as consumer demand for wireless data services drives wireless carriers to upgrade their current networks.

Yet despite its envious position, Crown Castle has not turned a profit during the last four fiscal years. Wireless infrastructure demands heavy investment in capital expenditures, and in Crown Castle's case, substantial debt for financing. It also means that the firm accounts for considerable depreciation in its earnings, as its wireless towers age and need to be renovated or replaced. Therefore, profits are hard to come by for Crown Castle.

Although it's unprofitable from an accounting standpoint, Crown Castle does possess solid operating margins and free cash flow. When you ignore the effects of depreciation, which does not affect a firm's cash position, Crown Castle seems well-equipped to service its considerable debt. However, that hefty burden has forced the company to get creative in the debt markets, offering asset-backed securities above its corporate credit's junk rating.

For Fools with an appetite for risk, Crown Castle may prove a winning pick. However, conservative investors should stay away. If Crown meets or exceeds its growth expectations, it will be a champ. But if it fails to do so, things could get ugly fast.

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Fool contributor Gerard Torres does not own shares in any of the companies mentioned in this article. Sprint Nextel is a Motley Fool Inside Value selection. American Tower is a Motley Fool Rule Breakers recommendation. Try any of our Foolish newsletters today, free for 30 days. The Fool disclosure policy sizzles on your plate.