Can a software company build its own smartphone? We may well find out soon.

Google last week completed its acquisition of the hardware maker Motorola Mobility for $12.5 billion, which could lead to the search giant's making its own smartphone.

But another software titan might be getting into the hardware game.

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 condition of anonymity for fear of repercussions.

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 website AllThingsD reported last year that Facebook and HTC had entered a partnership to create a smartphone, code-named "Buffy," still in the works.

Now, the company is expanding the group working on "Buffy," and exploring other smartphone projects, too.

When asked Friday, Facebook did not deny or confirm that a project to build a smartphone existed, but pointed to a previous statement it gave to AllThingsD last year that said in part, "We're working across the entire mobile industry; with operators, hardware manufacturers, OS providers, and application developers."

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.

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

The biggest names in consumer electronics have struggled with phone hardware. Hewlett-Packard tried and failed. So did Dell. Sony has never done very well making phones.

Despite the difficulties, Facebook seems well positioned in certain ways to enter the smartphone market. It has an entire operating system complete with messaging, calendar, contacts and video, and an immense app store is on its way.

There's also that billion-dollar camera app, in the form of Instagram.

If Facebook fails with its own team of engineers, it could buy a smartphone maker.

It could easily scoop up an infirm company like Research in Motion, which is valued at less than $6 billion, and drop a beautifully designed Facebook operating system on top of RIM's phones.