Google Calendar - Spend less time managing your day & more time enjoying it
Donte The Calendar - Send calendar invites using phone numbers
Mixmax Calendar - The fastest way to schedule meetings with anyone, anywhere
Planyway - Visual project management for Jira and Trello: manage resources, build project roadmaps, use time tracking.
Sunsama - Calendar and scheduling for teams
Calendar Screener - Rules to manage your calendar invites.