EventBus is the number 1 event library for android and java. EventBus uses the publisher and subscriber pattern for loose coupling which means the possibility of errors will be less. EventBus simplifies the communication between different components for example communications between different levels of activities or even services. You need very less or no setup to use EventBus in your existing project. EventBus provides a convenient annotation-based API which makes it fast and the performance is increased. EventBus is used by many popular apps, apps which has 1 billion-plus download which shows how EventBus popular. In this tutorial, we will see how we can get started using EventBus in an android project. Before jumping in the code let's see what we will be going to make. To better understanding EventBus we will make an app that allows us to add items to the cart and show the total count of the items. See below how our app will work. Let's