https://habrahabr.ru/post/344968/
Understand the APK structure
Reduce resource count and size
Reduce native and Java code
Maintain multiple lean APKs
Become an Android Painter
How to draw in Android
https://android.jlelse.eu/become-an-android-painter-aadf91cec9d4
Android, mvvm, databinding, custom adapters
Custom attributes using BindingAdapters in Kotlin
https://proandroiddev.com/custom-attributes-using-bindingadapters-in-kotlin-971ef8fcc259
Modeling ViewModel States Using Kotlin’s Sealed Classes
https://engineering.udacity.com/modeling-viewmodel-states-using-kotlins-sealed-classes-a5d415ed87a7
Simplify your Android code by delegating to sealed classes (https://medium.com/halcyon-mobile/simplify-your-android-code-by-delegating-to-sealed-classes-99304c509321)