Otherwise, the company has already worked with partners such as HTC to develop phones with tight software integration and a dedicated Facebook button, but they never succeeded, according to Jeronimo.

Reports in the New York Times and All Things D say that Facebook and HTC weren't put off by the failure of their jointly developed phones, named ChaCha and Salsa, and are working on new jointly developed devices. That makes more sense than going at it alone, Cozza said.

But a smartphone isn't the only route Facebook can choose if the company is bent on having its own hardware. A tablet is an alternative, because the tablet market isn't a set as the smartphone market, according to Cozza. However, young people aren't into tablets as much as smartphones, she said.

An alternative route to having more control over mobile phones is the further development of HTML5, which Facebook is also pushing hard. The vision for HTML5 is that applications can be developed to run in the browser instead of directly on the smartphone, and run on all devices. Changes that Facebook makes would affect more users than those of just its phone.