[on_and_off]

I am curious : on what kind of mobile apps are you working on your free time ?

By design, the NDK can only access a very small part of the platform APIs.

It is not an issue if you are making something where you are supposed to use the NDK (like a drawing app or a game), but for a 'traditional' app, that's another matter.

[pjmlp]

Very basic games or for the business logic with the UI done in Java and XAML - C++/CX.

But if Clojure did support properly Android and CoreCLR, I would probably use it instead.

As things are, I might go Xamarin in the future.

[on_and_off]

if you want multiplatform support (or just really like c#/VS), xamarin can be a good choice for an hobby app.

Otherwise, Kotlin borrows many niceties with c# and allows you to directly use the platform APIs.