From Java To Kotlin - Your Cheat Sheet For Java To Kotlin
Android Developer Roadmap - A complete roadmap to learn Android App Development
Square’s meticulous HTTP client for Java and Kotlin.
Java/Kotlin library to map locations or regions to time zones
LiquiCouch is a data migration tool for Java, Scala, Kotlin (or any other JVM lang) inspired by Liquibase
Stream Chat official Android SDK. The tutorial covers how to build your own chat experience using either Java or Kotlin.