I'm just upgrading the Ubuntu installation in my dual-boot Android/Ubuntu device. After I say "remove ubuntu" in the Ubuntu Dual Boot app (in preparation for reinstalling it, because system-image upgrades don't work in the dual-boot environment yet), I get taken almost instantly to a screen which looks like http://ubuntuone.com/3qJNpNEvcHGYerbSzJPe7s.
I've just spent five minutes looking at it waiting for the progress bar to fill up to tell me that it's finished deleting Ubuntu, until I realised that it deleted Ubuntu almost instantly and this screen is the "install a new version of Ubuntu" screen. That's... really confusing, especially since I don't understand what the big purple square in the middle of the window is for.
It would be much clearer if the app confirmed that the removal was done somehow, and that the screen linked above gave some indication of what it was for and what to do next.
I've mocked up what I think might be a clearer UI and attached the plain-text mockup. There may, of course, be use cases for the Dual Boot Android app that I don't know about; the menu is still present, which can give access to other user interactions.