Over the years, Android developers have been doing networking with the use of some APIs from the Android SDK and other tools which always involved a lot of work. The use of Retrofit became the standard when we are talking about consuming APIs. This means having an additional layer on top of Java and the logic of our app. With the introduction of Kotlin a few years ago and with their native support for asynchronous operations with Coroutines, developers were provided with tools easier to use.

First, for Java developers only

As Android developers, there are many ways to write an app and get tired of seeing how the lack of features of the Java (Java6 by default) platform embedded in the Android SDK slows the coding process. Notice that Java6 last public update dates from 2013 and that is the version you are expected to use on Android development with Java. You can use Java8 language features but most of the powerful features can only be used in devices that are running Android 7.0 Nougat (API 24).

By May 7, 2019, Android 10 not released yet, there was a total close to 41.9% devices running Android OS prior Nougat out of 2.5 billion active devices.