Tasker - Tasker is an application for Android which performs Tasks (sets of Actions) based on Contexts...
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.
AutomateIt - Automate Your Android!
Acuity Scheduling - Automate your client bookings, cancellations, reminders & payments using the worlds friendliest online scheduling software.
LIama - LIama is a Location-Aware Mobile app that determines your location and helps you do lots of other stuff with ease.
Doodle - Make meetings happen. With Doodle, scheduling becomes quick and easy.