Ask investors which smartphone stock they think is most important and they'll probably say Apple (Nasdaq: AAPL). And why not? The rise of the iPhone helped push Palm into the waiting arms of Hewlett-Packard (NYSE: HPQ) and eviscerated Nokia (NYSE: NOK) here in North America.

Yet I beg to differ. Apple is important, yes, but to me HTC is the most important smartphone stock (even though you can't buy it here in the United States). What Dell (Nasdaq: DELL) is to PCs, HTC is to smartphones and, increasingly, tablets. Here’s a look at the Taiwanese gear maker's latest deals:

  • HP, which had earlier confirmed plans to license the WebOS, is apparently on the verge of working with both HTC and Samsung on smartphones featuring the operating system.
  • HTC's Status, unveiled yesterday, brings to life the long-rumored Facebook phone. A built-in button activates all of the social network's key features, such as updating your status, posting a photo, or chatting with friends. MSNBC reports that AT&T (NYSE: T) will be first to carry the handset, which launches this summer.

HTC is also the designer behind the Thunderbolt, one of the fastest smartphones on the market for how it works with Verizon's (NYSE: VZ) 4G network. In some areas, the Thunderbolt has also outsold the iPhone 4. And finally, HTC preceded Apple in introducing the world to a touchscreen phone. Add it all up, and you have a smartphone supplier that works with every mobile OS vendor not named after a fruit, and which also challenges the iPhone in delivering advanced features.

So allow me to make a suggestion, investor to investor: If you want to know how the smartphone market is progressing and whether competing OSes are taking share from Apple, track HTC's shipment data, which is released quarterly.

Expect the second-quarter report next month. How is Q2 shaping up, you ask? Speculators quoted by Bloomberg this week say that HTC is on track to ship 11 million handsets, down from May estimates of 12 million. By contrast, analysts have pegged iPhone unit shipments between 15 million and 17 million for the current quarter. The implication? HTC may be chugging along fine, but Apple is still firing on all cylinders and looks to be about as strong a buy as you'll find in tech.

Yet my point remains: If you want to know how good Apple is performing relative to the rest of the smartphone industry, look no further than HTC's shipment reports.

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