Apps similar to ProcessOn include draw.io, which is free and open source. Other options are yEd Graph Editor, Dia, Pencil Project and Xmind. There's no shortage of Diagram Editors like ProcessOn, with more than 50 alternatives for Windows, the web, Mac, Linux and iPhone.
WhiteStarUML is a fork of StarUML with an intent to revive its Delphi code base by updating code to recent Delphi editions, reducing dependence on third party components and fixing bugs and adding new features.
Poland
EU
~ Simple way to view, annotate and share Microsoft Visio diagrams ~
United States
VSD Viewer opens Visio drawings directly on a computer without conversion on external Web Servers. Viewing Visio documents is as simple as dragging and dropping off files (with a .vsd, .vsdx, .vdx extension) to the Application window.
Ukraine
loud-based ADONIS:CE brings you just that, and helps build your digital twin. ADONIS:Community Edition will help you create BPMN diagrams, build your business architecture, and perform business process optimization.
AustriaEU
With YAKINDU Statechart Tools, you can easily create complex systems in a visual way. Simulate and test your system’s behavior already while you are modeling.
GermanyEU
Automatically connects to your Photoshop document and converts your mockups into interactive prototypes using layer comps to organize your documents into screens. Transition between them by defining hotspots in the layer name you want to be tappable.
UMLGraph allows the declarative specification and drawing of UML class and sequence diagrams. The current features are part of an ongoing effort aiming to provide support for all types UML diagrams.
GreeceEU
Grapholite is a powerful online solution for the creation of flowcharts, org charts, mind maps, Venn charts, web site structures, etc. Can be used online and offline
Ukraine
TopCoder UML Tool is an easy to use, consistent modeling tool for use in Design and Development competitions. The new tool was built to model sequence, class, use case, and activity diagrams. On top of that, all those elements can have documentation easily attached to them.
United States
Nevron Vision for .NET provides a complete set of components for data visualization that integrate with WinForms, Wpf, ASP.NET, and MVC applications.
BulgariaEU
Graphity is a diagram editor that can be used to quickly and effectively generate drawings and to apply automatic layouts to a range of different diagrams and networks.
GermanyEU
DBDesigner 4 is a visual database design system that integrates database design, modeling, creation and maintenance into a single, seamless environment.
GermanyEU
