Buddy Ohm - Buddy Ohm application
openHAB - "empowering the smart home" - vendor and technology agnostic open source home automation
RipplesIoT - Ripples provide wireless inventory tracking and asset monitoring solutions on the cloud for manufacturing, warehousing, construction, and healthcare industries.
Home-Assistant.io - Home Assistant is an open-source home automation platform running on Python 3.
The Thing System - The Thing System is an open source IoT platform.
ioBroker - flexible and modular application for the IoT and Smarthome