libqt4-designer 4:4.8.5+git192-g085f851+dfsg-2ubuntu4 (amd64 binary) in ubuntu trusty

 Qt is a cross-platform C++ application framework. Qt's primary feature
 is its rich set of widgets that provide standard GUI functionality.
 .
 The QtDesigner module provides classes that allow you to create your own
 custom widget plugins for Qt Designer, and classes that enable you to access
 Qt Designer's components.