Incredibuild - Turbocharges Development
It is a plug-and-play solution that empowers Qt users to dramatically reduce their Qt applications build times.
TreeView for Qt Quick
Provides a control that can be used to show a tree model in QtQuick.
The Qt Company
Advanced Docking System for Qt
Qt Advanced Docking System lets you create customizable layouts using a full featured window docking system similar to what is found in many popular integrated development environments (IDEs) such as Visual Studio.
Qt Android Tools
QtAndroidTools is a library that allows simplifying access to some native Android features from QML.
This is an extensive Qt5 Plotter framework (including a feature-richt plotter widget, a speed-optimized, but limited variant and a LaTeX equation renderer!), written fully in C/C++ and without external dependencies.
Qt Advanced Stylesheets
Advanced Stylesheets with Theming Support for Qt.