Canonical has revealed advanced plans to offer a version of the Ubuntu Unity desktop running as a tightly integrated environment inside Android smartphones.

If this sounds like an unexpected hybrid, the thinking behind it is that users will be able to interact with Android as the primary interface for things like phone calls and texting but fire up and dock Ubuntu to a screen and keyboard using HDMI or the emerging Mobile High-Definition Link (MHL) to use as a working desktop OS when needed.

Ubuntu will be pre-installed on Android smartphones by handset makers, hooking into the common Linux elements shared by Ubuntu and Android to fully integrate the two environments. Android apps appear as icons on the Ubuntu for Android Unity desktop, in addition to a suite of Ubuntu programs familiar to users of the OS.

Applications on the two would also be integrated, allowing (for instance) an Ubuntu calendar app to see contacts that were entered through Android.

According to Canonical founder Mark Shuttleworth the advance in smartphones that makes putting Ubuntu on Android possible is the dramatic increase in their power. Multi-core ARM chips running at clock speeds over 1GHz now offered power that could be efficiently deployed to transform smartphones into parallel desktop environments when combined with cloud services.

“The desktop is the killer-app for quad-core phones in 2012. Ubuntu for Android transforms your high-end phone into your productive desktop whenever you need it,” said Shuttleworth.

He stressed that Ubuntu for Android was fully integrated and used no virtualisation – Ubuntu and Android would run at full tilt side-by-side. Although Ubuntu would not be identical to the desktop version (you can't obviously install Intel-based apps) it would offer enough of the OS to make using it powerful.

With its (to some) contentious Unity interface, Canonical has recently turned into a hive of ideas as to how its version of Linux can be reinvented to suit a world in which desktop and laptops are no longer the central computing devices for consumers and even business users.

In recent months this has included talking up the potential of Ubuntu on Internet TVs, and even introducing a ‘heads up’ search to interact with applications and the OS instead of traditional menus.

Ubuntu for Android looks like lateral take on Shuttleworth’s long-time promise that Ubuntu would run on smartphones, which everyone assumed to mean that the company would offer a full-fledged smartphone OS.

This standalone smartphone OS plan was still being developed, he said, but in the meantime the company saw immense value in levering its OS to extend what smartphones could do.

Canonical was currently working with undisclosed handset makers and hoped to have Ubuntu for Android for sale towards the end of 2012, Shuttleworth promised.