The author created a smart baby monitor using a Raspberry Pi, Python programming language, Twilio SMS API, and peripheral sensors. The IoT app will use the Raspberry Pi to live stream video over the WiFi network, take temperature readings from a DS18B20 sensor, and send text messages if the temperature falls above or below a threshold. The author provides step-by-step instructions on how to set up the hardware and software components of the smart baby monitor, including configuring the Raspberry Pi, connecting peripheral devices, enabling the Web Cam Interface, installing the Twilio client, and writing Python code to read temperature data from the sensor and send text messages.