Employees of Facebook and several engineers who have been sought out by recruiters there, as well as people briefed on Facebook’s plans, say the company hopes to release its own smartphone by next year. These people spoke only on the condition of anonymity for fear of jeopardizing their employment or relationships with Facebook.

The company has already hired more than half a dozen former Apple software and hardware engineers who worked on the iPhone, and one who worked on the iPad, the employees and those briefed on the plans said.

This would be Facebook’s third effort at building a smartphone, said one person briefed on the plans and one who was recruited. In 2010, the blog TechCrunch reported that Facebook was working on a smartphone. The project crumbled after the company realized the difficulties involved, according to people who had worked on it. The Web site AllThingsD reported last year that Facebook and HTC had entered a partnership to create a smartphone, code-named “Buffy,” which is still in the works
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For Facebook, the motivation is clear; as a newly public company, it must find new sources of revenue, and it fears being left behind in mobile, one of the most promising areas for growth.

“Mark is worried that if he doesn’t create a mobile phone in the near future that Facebook will simply become an app on other mobile platforms,” a Facebook employee said.

Facebook is going to great lengths to keep the phone project a secret, specifically not posting job listings on the company’s job Web site, but instead going door-to-door to find the right talent for the project