February has been a fairly busy month for the Mozilla Corporation and, since February ends with Mobile World Congress, the announcements keep coming — especially since the company is still in the process of rolling out its new mobile operating system. Indeed, Mozilla made it known this week that its Firefox OS will be supported by 18 mobile operators around the world, including Sprint in the U.S.

The other tidbit of news surrounding Firefox OS was the release of Twitter for the platform, meaning early adopters interested in this HTML5-heavy platform will be able to download its official Twitter app right away. According to Twitter's official blog, Twitter for Firefox OS sports a very similar interface to other mobile incarnations, featuring the standard Home, Connect, Discover and Me tabs — as well as the ability to search and compose tweets, of course.

However, Twitter for Firefox OS will also boast a new, exclusive feature called Web Activities. Web Activities actually sounds pretty neat as it allows users to tweet photos directly from any app that also supports Web activities. Currently, the platform's built-in photos app supports this feature, but it's very likely that other apps will also enable it.

Mozilla also recently released a pair of developer preview phones, called Keon and Peak, developed in partnership with Spanish smartphone manufacturer Geeksphone. As developer preview devices, neither Keon nor Peak will likely ever make it into the hands of consumers, instead being used to help developers build and preview their own apps.

Meanwhile, on the desktop front, Mozilla has been making a number of advancements with the Firefox browser, the most significant of which is the introduction of WebRTC support on Firefox Nightly and Aurora releases. This means that full WebRTC support should soon make its way to a stable release of Firefox, furthering the spread of plugin-free, real-time browser-based chatting.