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.
Home-Assistant.io - Home Assistant is an open-source home automation platform running on Python 3.
Meetingbird - Powerful meeting scheduling and notes — right in your calendar
ioBroker - flexible and modular application for the IoT and Smarthome
Clara - Clara is a virtual employee that schedules your meetings, getting you to the work that matters, faster.
openHAB - "empowering the smart home" - vendor and technology agnostic open source home automation