MyApplication.java

public class MyApplication extends Application {

    @Override
    public void onCreate() {
        super.onCreate();
        if (BuildConfig.DEBUG) {
            RxJavaPlugins.getInstance().registerErrorHandler(new RxJavaErrorHandler() {
                @Override
                public void handleError(Throwable e) {
                    Log.e("UnhandledError", e.getMessage(), e);
                }
            });
        }
    }
}