HTC today reported a sharp increase in profits for the third quarter of 2011, driven by an almost doubling of its smartphone shipments. However, its guidance for the next period caused some concern, with it anticipating sequential declines in device shipments and sales.

For the quarter, the company announced a net profit of TWD18.68 billion (US$624.3 million), up 68 percent year-on-year, on revenue of TWD135.82 billion, up 79.1 percent. It shipped 13.2 million devices, up 93 percent year-on-year.

However, it was noted that the company’s revenue guidance for the fourth quarter (TWD125 billion–TWD135 billion) will mark a sequential decline for the lucrative Christmas holiday sales period (although up 20 percent–30 percent year-on-year).  It expects to ship 12 million–13 million smartphones, up 31 percent–42 percent year-on-year, but down slightly from Q3.

According to reports, HTC is facing uncertain demand following the launch of new devices from itself and its rivals. In addition to Apple’s iPhone 4, Nokia is also set to launch its first Windows Phone handsets in the near future – and new smartphone market leader Samsung is also a tough competitor.

The Taiwan-based company is also facing a tough economic situation in many of its European markets, which is affecting consumer confidence.

HTC launched a number of new products in the third quarter, including the Sensation XE and Sensation XL multimedia smartphones, Rhyme social lifestyle device, and Explorer entry-level terminal.

It noted that Asia sales grew strongly, with China reporting the strongest increases among all regions.

It was also reported that HTC said it will not move away from its smartphone niche into low-end devices, as had been suggested previously. It is instead looking to capture business from existing feature phone users trading-up to smartphones.