There is a post at https://wiki.ubuntu.com/Touch/Install?action=show&redirect=TouchInstallProcess where you can read about the process installation for Ubuntu Phone on Galaxy Nexus (some models). But, is possible do this on a Galaxy S II? Thanks for your time. Sergio.
1 Answer
If you look here it will show a list of devices that Ubuntu touch is working on: https://wiki.ubuntu.com/Touch/Devices. And on the list is the Samsung Galaxy S2, and then if you click on the link you are taken to https://wiki.ubuntu.com/Touch/Devices/i9100 which shows the current status and how to install it.
Hope it helps