Calendly

Calendly is a US scheduling-automation platform founded in 2013 by Tope Awotona and headquartered in Atlanta, Georgia. Users share a personal booking link that lets others pick open slots against their connected calendar, with automatic invites, reminders, time-zone handling, round-robin team routing, and payment collection. It became one of the most widely used booking tools, valued around $3B, and is the mainstream incumbent the European alternatives here are measured against.