What is Ubuntu For Android?

Solution 1:

It's not a "mobile version" of Ubuntu.

It's a special build of the Ubuntu OS that can be installed on Android dual-core phone, with this you can attach a HDMI monitor (and I think a bluetooth keyboard and mouse) and use your smartphone as a computer with Ubuntu.

As an extra, from that desktop you can access to phone data (like addressbook) and send / receive calls.

I think that this image clarify what is it:

Official page for more info: http://www.ubuntu.com/devices/android

Solution 2:

It's similar to the Motorola devices webtop app that recent devices have.

You dock it and use your mouse and keyboard to use it as a desktop.

Coincidentally, Motorola has been using Ubuntu for a year on webtops.