Languages for writing client side apps have always sucked. They sucked in the 90's when targeting Windows (ok Delphi wasn't too bad), they sucked in the 2000's when targeting MacOS X and they suck now when targeting mobile. Of all the languages that mainstream operating systems have used, Java is by far the least worst. Especially because you can use any JVM-compatible language and are not really restricted to Java. For example Kotlin is looking like it's going to be pretty nice, pretty soon.
Go would be nowhere near a useful upgrade on the status quo.
Languages for writing client side apps have always sucked. They sucked in the 90's when targeting Windows (ok Delphi wasn't too bad), they sucked in the 2000's when targeting MacOS X and they suck now when targeting mobile. Of all the languages that mainstream operating systems have used, Java is by far the least worst. Especially because you can use any JVM-compatible language and are not really restricted to Java. For example Kotlin is looking like it's going to be pretty nice, pretty soon.
Go would be nowhere near a useful upgrade on the status quo.