Meetingbird for Gmail - View your calendar and schedule meetings right from Gmail
Whatspot - Simple booking system for spaces in companies. Use app to reservations of meeting rooms, car fleet.
Kin Calendar - The simple and connected calendar
Task Muncher - Task Muncher is a cross-platform and web-based application that is designed to organize and keep the track of everything and focus on munching the weekly tasks.
Calendly for Chrome - Schedule meetings without leaving your inbox
Taskable - Using multiple work apps leads to tons of context switching, breaking flow and killing productivity.