Java or kotlin for android mobile development ? And why ? I am still not convinced by kotlin at least just by myself but is it worth it ?

Kotlin.
Java is a terrible language. Kotlin makes the JVM a little bit less terrible.

@kescherRant what the difference ? In short

@Mba3gar Nullsafety, functions outside of classes, no primitive types (e.g. not Java int, but only Integer), syntax (obvoliously).

As both use the same JVM, you can mix both languages.

For a detailed comparison, you might want to look at the Kotlin documentation's documentation's page "Comparison to Java Programming Language": https://kotlinlang.org/docs/...

Also a built-in UInt!

Kotlin is awful with 0 non-basic documentation, and java is stuck on 6.

Use react native, i dont like it either but i feel like thats the least bad option.

@yellow-dog well react native cant reach level as expectations

What

Html will probably works