Apache Kafka is being used by the author in their Spring Boot application to process huge amounts of data in real time, handling millions of messages per second. The author recommends using Confluent CLI for development and provides a step-by-step guide on how to include Apache Kafka in a Spring Boot application. The guide covers generating a project, publishing/reading messages from the Kafka topic, configuring Kafka through an application.yml configuration file, creating a producer, consumer, and REST controller. With these steps, developers can start leveraging the benefits of Apache Kafka in their own projects.