Based on our record, NClass seems to be more popular. It has been mentiond 1 time since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
Yet, there are plenty great tools for UML diagrams: StarUML, NClass, PlantUML and plenty others. Source: almost 2 years ago
yEd - yEd is a free desktop application to quickly create, import, edit, and automatically arrange diagrams. It runs on Windows, Mac OS X, and Unix/Linux.
SequenceDiagram.org - Clean and fast online sequence diagram tool using scripting and Drag and Drop
draw.io - Online diagramming application
PlantUML - PlantUML is an open-source tool that uses simple textual descriptions to draw UML diagrams.
LucidChart - LucidChart is the missing link in online productivity suites. LucidChart allows users to create, collaborate on, and publish attractive flowcharts and other diagrams from a web browser.
WebSequenceDiagrams - WebSequenceDiagrams is a web-based application that allows the user to use a proprietary language to define sequence diagram.