The Samsung Galaxy S III may not be the only non-Nexus phone running Ubuntu Touch Preview for long. Canonical has posted instructions for porting Ubuntu Touch to run on pretty much any Android phone or tablet.
It turns out the process is pretty straightforward: Because most of the hard work has already been done by the developers behind the popular CyanogenMod custom ROM for Android devices.
Ubuntu Touch relies on a stripped-down version of CyanogenMod 10.1 for its Linux kernel, and support for hardware including audio, video, graphics, and modems.
So the Ubuntu Phablet git repository is actually just a mirror of CyanogenMod 10.1, but without features that aren’t needed such as Dalvik (the Java virtual machine that actually lets you run Android apps on an Android device).
CyanogenMod is capable of running on dozens of Android phones and tablets. And if you’ve got a device that can run CyanogenMod 10.1, you’ve pretty much got a device that can run Ubuntu Touch.
All you need to do is build a custom ROM for your device by following the instructions at the Ubuntu Wiki by basically building a custom version of CyanogenMod plus Ubuntu Touch running in a separate container. When you boot into Ubuntu Touch, you’re kind of booting an Android operating system which accesses the Ubuntu system via chroot so that you get an Ubuntu user interface instead of a typical Android UI.
While the process isn’t much different than building CyanogenMod from source, it’s not exactly a beginner-friendly project. But if the instructions are a little over your head, I suspect you may not have to wait long until a version of Ubuntu Touch is available for your Android phone or tablet.
Just keep in mind that Ubuntu for phones and tablets is still a pre-release preview at this point. Many features aren’t yet fully functional and the OS can get pretty sluggish at times.
Update: You can find a list of phones and tablets that can run Ubuntu Touch Preview, as well as works-in progress, at the Ubuntu Wiki.