Patches are always welcome! Please submit your patches via the Ubuntu Phone mailing list (ubuntu-phone@lists.launchpad.net).
You can find more information about the mailing list and the Launchpad ubuntu-phone team at https://launchpad.net/~ubuntu-phone.
To get started with Ubuntu Phablet Android build, you'll need to get familiar with Git and Repo.
To initialize your local repository using the Ubuntu Phablet trees, use a command like this:
repo init -u git://github.com/HTCUbuntu/android.git -b phablet-10.1
Then to sync up:
repo sync
Please see the (http://wiki.ubuntu.com/) for building instructions.