What part of Java is in mobile development if the code is written in Kotlin?

Question

Mobile development

Why do you need to know Java if applications are written in Kotlin?

Is it just that if you are interested in mobile development, is it necessary to start with Java?
Is it the same situation with Swift? Or is there only swift and that's it?

Help me to understand.

Answer 1

It is not necessary to start with Java, you can start with Kotlin right away.
Kotlin for Android compiles to Java bytecode. It also uses the Java standard library (collections, for example). Therefore, you will encounter Java one way or another, but, in principle, you can smoke it along the way, it is not necessary to suffer from the very beginning. When the level of your competence grows, you will understand where the gaps are and what you do not understand. Then you will learn Java and the jvm device.
Swift in ayos in the first couple is enough with his head. There is Objective-C, but you will not encounter it, unless you get into something low-level.