SceneBuilder 26.0.0
Scene Builder is free and open source, but is backed by Gluon. Drag & Drop user interface design allows for rapid iteration.
Gluon software
DlSoftware247 lists 2 Windows programs by Gluon, mostly Programming Languages, Graphic & Design software. The most popular are SceneBuilder, SceneBuilder 18.
SceneBuilder 18 18.0.0
Scene Builder is free and open source, but is backed by Gluon. Drag & Drop user interface design allows for rapid iteration.