If you know of good examples where MQTT is in use, please add them here.

Further examples are described in comments to a post Do you use MQTT? on the mosquitto blog.

• Gaian DB a distributed database
• Location Aware Messaging for Accessibility, LAMA an IBM Extreme Blue Project
• Say It, Sign It (SiSi) an IBM Extreme Blue Project
• Relayr uses MQTT to connect with the Wunderbar and other IoT devices.
• Owasys AVL is a fleet management service providing real-time tracking and event information efficiently using MQTT and owa11A devices.
• flespi relies on MQTT in internal communications between services.

• Andy SC's Twittering / Automated House
• Power monitoring
• Lighting control
• Gardening
• energy monitoring with an old-style analog ammeter
• Android/TV/Burglar detection system
• MQTT<>LLAP bridge example for the Ciseco OpenKontrol Gateway
• WarmDirt project to control soil temperature for plants (like potatoes!)
• homA - An extensible framework for the smart home
• homebridge-mqtt - A Plugin for Homebridge

• Southampton University LEGO microscope controller
• Messaging protocol applications research at CEIT, University of Queensland
• FloodNet Southampton University
• Smart Lab Southampton University
• mobile4D disaster alerting system, University of Bremen

• Facebook Messenger
• Thread Dating using ClearBlade

• Check out the Tools overview for details.

• Christmas lights
• Mind controlled taxis
• Glowing rubber ducks