Motion Firefox - All-in-one time management tool in Firefox
Button for Google Calendar™ - See your daily schedule and join meetings in one-click.
FocusList - Daily planner & focus timer based on timeboxing and pomodoro
Calndr.link - Dead simple & free add to calendar links + API
Teeny Breaks - Mindfulness tips to make the most of your breaks 🧠💖
Add-to-Calendar Button Generator - This open source projects lets everybody create amazing buttons, where users can add events to their calendars.