Some of the best times to buy stocks are during historically tumultuous times, and the mess the market is in surely counts as one. Especially with a proven market leader like mobile phone company Nokia (NYSE:NOK), there are many reasons to consider buying shares.

In our Motley Fool CAPS community, an impressive 2,555 out of more than 130,000 investors have given an opinion on Finland's Nokia, saying they're bullish or bearish. Weeding through the detailed information packed in pitches and other comments, here are three of the top reasons many members see Nokia as unstoppable today:

International strength: Competition may be fierce from Apple (NASDAQ:AAPL), Research In Motion (NASDAQ:RIMM), and even Google (NASDAQ:GOOG) in the U.S., but Nokia still dominates in worldwide smartphone sales. And though it dominates the cell-phone market, Nokia still has big potential for growth in developing markets like China, where its Nokia Siemens partnership recently helped China Mobile (NYSE:CHL) roll out new technology.

Strong fundamentals: Nokia is a machine that has generated more than $3.2 billion in free cash flow over the past year. The company may not be showing the same growth it has in the past, but it maintains a strong balance sheet at a time when some peers are struggling. But finding a good company like Nokia or Texas Instruments (NYSE:TXN) that is backed by strong fundamentals isn't the best part -- finding them at cheap valuations is.

Domestic potential: Even with Nokia's worldwide market leadership, it still has just a small part of the U.S. market. Though many investors lament the past failures to break into one of the most lucrative markets in a big way, Nokia and its partner Siemens AG (NYSE:SI) may be looking to change that with a bigger presence in the North American market via Nortel's assets.

Of course, there's a lot more devil in the details of these buy-side opinions. That's why CAPS is such a great resource to balance your own analysis -- a place where you can consider the bullish and bearish sides to every stock. To see what the best CAPS members are saying now about Nokia, just click on over to Motley Fool CAPS and have a look.

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