Intercom - Intercom is a customer relationship management and messaging tool for web businesses. Build relationships with users to create loyal customers.
Home-Assistant.io - Home Assistant is an open-source home automation platform running on Python 3.
Drift - A messaging app that helps you grow your business.
ioBroker - flexible and modular application for the IoT and Smarthome
Crisp Chat - Multi-channel customer support software
openHAB - "empowering the smart home" - vendor and technology agnostic open source home automation