Isometric - Create beautiful, abstract works of art & optical illusions
draw.io - Online diagramming application
Grid Paint - Online grid-based paint program offering squared, triangular, and hexagonal grids.
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.
Indie Boost - A video game discovery software used by Publishers, Press, YouTubers, and Streamers.
PlantUML - PlantUML is an open-source tool that uses simple textual descriptions to draw UML diagrams.