Timestead - Job Sheet and Jog management software as a service.
Time Slot Booking Calendar PHP - Time Slots Booking Calendar PHP for online appointment booking and class scheduling.
AroFlo - Job management for trade services & project based industries
Pulse 24/7 - Booking & scheduling mobile app for service providers
Fieldax - Field Service Management - Best Field Service Software for Small and Medium Field Service Businesses
Dudle - Dudle is an online scheduling application, which is free and open source.