Alongside the big four, we now have Ubuntu, Firefox OS and the latest version of Tizen all elbowing each other for room.

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What excites me most is the desktop convergence and the fact that Ubuntu is now an OS that can seemingly exist anywhere thanks to its ability to scale.

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The Unity Next project will incorporate several core components from the Ubuntu Touch interface, inching the Linux OS closer to its goal of a truly unified codebase.

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Canonical hopes that future devices (read: arriving sometime in 2014) will not only run the new mobile OS, but will also boot the desktop variant of Ubuntu when docked to a keyboard, mouse and monitor.

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Tizen's mostly likely rival will be Ubuntu, at least once that other Linux-based OS progresses beyond entry-level phones at some point in 2014.

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Another new phone OS that will be previewed later this month and will arrive later in 2013 is Ubuntu from Canonical.

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The other option is Ubuntu for smartphones from Canonical, which brings the mega-popular open source OS to mobile devices, specifically those designed for Android.

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The other big news is Ubuntu Light, which is Canonical's take on an instant-on OS, and is targeted directly at OEMs for use on netbooks and other mobile devices.

ENGADGET: Canonical shows off 'Unity' desktop, Ubuntu Light for OEMs