Fantastical 2 - Fantastical, the Mac calendar app you'll enjoy using. Quickly create new events with natural language input and more.
Microsoft Outlook - Organize your world. Outlook’s email and calendar tools help you communicate, stay on top of what matters, and get things done.
BusyCal - powerful calendar app for macOS
Google Calendar - Spend less time managing your day & more time enjoying it
Apple Mail - There’s big news attached.
Superpowered - Power through the day without your calendar