Productivity

Calendar app (discontinued, but listed as example).

Diagram and flowchart maker.

A free diagramming tool for creating graphs and diagrams.

Online diagram and flowchart tool.

Fast calendar app for power users

Mind mapping app for capturing and organizing ideas.

Calendar and scheduling tool

Mind mapping app for iOS and macOS.

Calendar app for Mac

Eisenhower Matrix for productivity.

Pomodoro timer for focus and productivity.