The first requirement is you need to own a rooted Android phone in your hand, and then download Ubuntu Installer, to easily install Ubuntu to your rooted Android phone.
To get you deeper on what you will get once it's installed to your device, here is a key features list.
- Run Ubuntu within Android.
- Access to both Android & Ubuntu at same time.
- Highly optimized for ARM devices.
- LXDE Desktop (very lightweight)
- Ubuntu update manager, Software centre fully operational.
- File system access: Ability to access files on your SD card and internal memory from Ubuntu.
- Set resolution: Ability to set screen size on boot (you no longer have to download a certain image for different screen sizes!)
- Choose Ubuntu Installation type: ‘large’ and ‘lightweight’
And you will be able to boot into LXDE desktops or Gnome instead, there are many apps provided to be developing like Thunderbird, Firefox, GIMP Image Editor, Openoffice.org and more.
If you are interested to install Ubuntu to your Android device, then you can download Ubuntu Installer from Android Market here.