Anyone have much luck with browser sync and external URL?

I can’t even get the UI external to work so wondering if there’s something i’m missing? Would be great to get this working!

[BS] Watching files…

gulp settings…

    gulp.task('watch', function() {
    files: ['{lib,templates,templates-misc}/**/*.php', '*.php'],
    notify: false,
    watchTask: true,
    proxy: config.devUrl,
    host: "",  
    snippetOptions: {
      whitelist: ['/wp-admin/admin-ajax.php'],
      blacklist: ['/wp-admin/**']
  });[path.source + 'styles/**/*'], ['styles']);[path.source + 'scripts/**/*'], ['jshint', 'scripts']);[path.source + 'fonts/**/*'], ['fonts']);[path.source + 'images/**/*'], ['images']);['bower.json', 'assets/manifest.json'], ['build']);

if any other info would be helpful please let me know & any help appreciated.