Home Air Quality Monitoring (Part 2)

The Android Application Raul continues his article series on building a home air quality monitoring system based on Nordic Semi’s nRF5340 dev kit. In Part 2, he discusses the mobile app that he modified to interact with the IoT device and the web server. Topics Discussed How to building an IoT-based home air quality monitoring systemHow to install the necessary software toolsHow the monitoring system functionsHow to add the sensor driversHow to send data over BLEHow to implement the display and touchscreenHow to implemented running average, low-pass filters Tech Used Nordic Semi’s nRF5340 dev kitCCS811 eCO2/eTVOC sensor from AMS Sharp GP2Y1010AU0F dust/particle sensor (from Sparkfun)STMicroelectronics LPS22HB barometric pressure sensorDHT22 ambient temperatureRelative humidity sensorArduino Mega2560 prototyping shield SEGGER J-Link programmer/debugger2.8″ TFT Touch Shield for Arduino w/Capacitive Touch In Part 1 of this article series (Circuit Cellar 378, January 2022) [1], I discussed the IoT device prototype for the Home Air Quality Monitoring (HAQM) system. The IoT device is based on Nordic Semiconductor’s nRF5340 Development Kit (DK), it uses air quality sensors to collect data, and a wireless Bluetooth Low Energy (BLE) connection to send them to an Android device. The IoT device reads its sensors every 1-2 seconds (depending on the sensor), and sends the data every 5 seconds to the Android mobile device. The mobile device, in turn, takes the sensor readings and sends them to a web server by using the HTTP protocol. Here, in Part 2 of the series, I discuss the mobile application that I modified to interact with the IoT device and the web server. I took as a basis the nRF Toolbox for Bluetooth LE Android application from Nordic Semiconductor, which is available for download as an Android Studio source code project [2]. To follow this article, you will need to have a fair knowledge of Android application development with the A