Ubuntu Touch Developer Preview has been released for some time now, but it's only working on a very select number of devices. The community has stepped in and the number of devices has increased exponentially.
A lot of people have gone out of their way to port the new Ubuntu Touch Developer Preview for their devices and so far, there are 36 projects opened.
Canonical also published a comprehensive porting guide and has invited everyone with the necessary knowledge to participate.
“We want to port Ubuntu Touch to all kinds of devices. If you have experience in porting code to Android devices or are generally knowledgeable in terms of porting, working with the Kernel and other core bits and pieces of a distribution, this might be interesting to you,” states the official announcement
If you want to contribute, you should check out the list of opened projects