I created a BLE-MQTT bridge for the Hackday project, and my team showed a fun example of how it can be used for home automation. The BLE sensors used Silicon Labs BGM111 to sense when windows and doors are opened. The module controlling the mini house was an ESP8266 connected via MQTT. Jake Scearcy built the mobile app using NativeScript, and Vu Nguyen did the 3D printed design for the house. Here’s the Project Page. Our project was voted first place.