Donte The Calendar - Send calendar invites using phone numbers
Calendly - Say goodbye to phone and email tag for finding the perfect meeting time with Calendly. It's 100% free, super easy to use and you'll love our customer service.
Planyway - Visual project management for Jira and Trello: manage resources, build project roadmaps, use time tracking.
Cal.com - Cal.com (formerly Calendso) is the open source Calendly alternative.
Calendar Screener - Rules to manage your calendar invites.
SavvyCal - A scheduling tool both the sender and the recipient will love.