Kotlin a somewhat recent addition to the Android Development platform. Designed to replace Java being the language of requirement at the time to create Android applications.
Providing you have access to the original source and are the owner, we will be happy to take on any amalgamations you might seek to acquire.
Perhaps you have an existing applications performing sluggishly, those few seconds can make a whole lot of difference to the end user, especially if your in a competitive market.
Generally with Android applications, from scratch, we expect to see a Wireframe or Visual Flow on how you would like the application to look.
Having this ready will speed up the time it takes to get your app off the drawing boards and into the app store.
On Android this can be fairly, quick.