Kotlin can generate both JVM bytecode and iOS binaries. I've successfully shared code between iOS and Android projects using Kotlin before. The overhead is quit

Kotlin can generate both JVM bytecode and iOS binaries. I've successfully shared code between iOS and Android projects using Kotlin before. The overhead is quite low, and, all in all, I was quite satisfied with the results. However, a lot of the tooling around this is experimental, so you might want to tread carefully here.