Our device is now ready to receive messages via MQTT. The MQTT server we are using features an MQTT, as well as an HTTP-interface. There are many different ways that we can now send messages to our device:
- Via Terminal/PowerShell as MQTT messages using an MQTT client such as Mosquitto
- Via Terminal/PowerShell as HTTP messages using curl
- Via a third-party iOS/Android app
- Via a third-party macOS/Windows/Linux app
- Via a third-party web-based client (for example, http://www.hivemq.com/demos/websocket-client/)
- Via a custom-made website using a JavaScript-MQTT client
- Via a custom Android/iOS/macOS/Linux/Windows app using MQTT-client
Basically everything is possible depending on how you send text to your device. MQTT is amazing!
Because programming a custom app would be a bit much on top of what you have already learned, we will focus on the easier...