Viso - Beautiful minimal image viewer for MacOS
draw.io - Online diagramming application
LightGallery - A modern, electron and nodejs based image viewer for Mac, Windows and Linux.
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.
Tiat - A simple and powerful image organizer 🖼️
PlantUML - PlantUML is an open-source tool that uses simple textual descriptions to draw UML diagrams.