Chart.js - Easy, object oriented client side graphs for designers and developers.
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.
D3.js - D3.js is a JavaScript library for manipulating documents based on data. D3 helps you bring data to life using HTML, SVG, and CSS.
Acuity Scheduling - Automate your client bookings, cancellations, reminders & payments using the worlds friendliest online scheduling software.
Google Charts - Interactive charts for browsers and mobile devices.
Doodle - Make meetings happen. With Doodle, scheduling becomes quick and easy.