Is it possible to build a keyboard with KMM? If so do you recommend sharing the UI later or separate for iOS?

It should be possible but why you need this ?

I wanted to build a custom keyboard and work on both platforms. It make API requests etc just like Gboard..

What is KMM?

Kotlin Multiplatform Mobile. That's what Jetbrains called it a year ago. I haven't done native stuff since then. https://lp.jetbrains.com/kmm-for-crossplatform-developers/

Oh, I get it, you mean KMP!