Fluid UI is a browser-based wireframing and prototyping tool developed by Fluid Software and used to design mobile touch interfaces.
License: Freemium
Fluid UI is primarily focused on prototyping and UI design, making it ideal for designers needing a simple and intuitive tool for creating user interfaces. In contrast, draw.io is a comprehensive diagramming tool that excels in creating various types of diagrams, making it suitable for technical and non-technical users alike.