Whether you are a professional programmer or a hobbyist, programming an Android app is an attractive proposition. Android firmly dominates the global smartphone market, meaning many potential users. All the tools you need are free to download and use and it’s easy to get started as Android Studio will build you a Hello World app in a few minutes. What you do next is more difficult as Android is a tough system to master and to create a good app you need a feel for how the system works and its limitations. The good news is that Kotlin is a language that makes working with Android much easier.