Of all the calendar apps on macOS, Apple’s built-in calendar is probably the most widely used. So let’s get down to it: what’s the best calendar app for the Mac? Apple’s Calendar I keep all my tasks in a separate app, so I only use it for appointments. I have my way of managing my calendar, and that will undoubtedly skew my opinions. Like I always say when I write articles like this, this is purely based on opinion for me. Others only have their official meetings. Some people like to manage all of their tasks from it. I know that everyone uses their calendar in different ways. What’s the best calendar app for the Mac?.