From a few years ago, with Scala 2, but the fundamentals may not have changed much.
Scala had, and has, a large bespoke standard library, which is big enough that if you tried to ship it with even a trivial app, it exceeded limits not just on memory, but on numbers of classes, methods, and so forth. (And even if those limits have been raised on newer phones, older ones are still a nontrivial market segment.)
So the way people got around that was by using "tree shakers", which would grovel through the app and its libraries, and chuck out portions of the library which weren't actually used. This works, but significantly complicates the development toolchain.
Between that and the official support for Kotlin as the "better Java" dialect of choice, you have to really like Scala to make it worth the effort...
Scala had, and has, a large bespoke standard library, which is big enough that if you tried to ship it with even a trivial app, it exceeded limits not just on memory, but on numbers of classes, methods, and so forth. (And even if those limits have been raised on newer phones, older ones are still a nontrivial market segment.)
So the way people got around that was by using "tree shakers", which would grovel through the app and its libraries, and chuck out portions of the library which weren't actually used. This works, but significantly complicates the development toolchain.
Between that and the official support for Kotlin as the "better Java" dialect of choice, you have to really like Scala to make it worth the effort...