Doodle - Make meetings happen. With Doodle, scheduling becomes quick and easy.
Yahoo! Calendar - You can view an entire month or focus on a specific date and time.
The Receptionist - The Receptionost is a visitor managemnt solution that has visitor logging system to track visitor traffic.
Google Calendar - Spend less time managing your day & more time enjoying it
Qminder - Qminder works the way it sounds: It helps a company mind its queues.
Fantastical 2 - Fantastical, the Mac calendar app you'll enjoy using. Quickly create new events with natural language input and more.