Whimsical
whimsical.com
A visual workspace for wireframes, flowcharts, mind maps, and sticky notes with a fast, minimal interface designed for thinking out loud.
Why it is useful
Has the best balance of speed and output quality for rapid diagramming — you can go from blank canvas to a complete flowchart in minutes with far less friction than Lucidchart or draw.io. The wireframe components are opinionated enough to look clean without needing design skills. Free for individuals with enough capacity for serious work.