Meetsy

Create your own polls - Terminplaner 4.1

Easy!Appointments – Open Source Appointment Scheduler

Cal.com | Open Scheduling Infrastructure

PeachPay - Monetize your Content

CoreUM - The Ultimate Meeting Application

Polymail — Email Tracking, Templates, Send Later, and Calendar Integration

Calendly - Scheduling appointments and meetings is super easy with Calendly.

Meetin.gs - Free, Easy and Better Online Meeting Organizer

World Time Buddy - Ridiculously easy world time and meetings across time zones!