Ubuntu Tweak is a third-party application designed to make configuring Ubuntu easier for everyone.
Ubuntu Tweak is a popular third-party application meant to make configuring Ubuntu easier for everyone. It offers similar functionality to apps such as GNOME Tweak Tool, MyUnity, the Software Center, and others - all in one utility.
It provides several desktop and system options, some of which cannot otherwise be changed through Ubuntu's default interface. With it, a user can alter their desktop's appearance, carry out various administrative tasks, manage software sources, clean unwanted packages, etc.
As of October 19, 2012, the app's author announced that Ubuntu Tweak development has stopped. The last available version is for Ubuntu 12.10. Note that the application still mostly works (with the exception of the Apps tab), but no bug fixes or newer versions will be released.
See How do I install Ubuntu-Tweak? for installation instructions.