gulpManifests.js

// Bundle manifest
var manifest = {
 
  styles: [
    './www/lib/ionic/css/ionic.css',
    './www/lib/fontawesome/css/font-awesome.css',
    './www/less/index.less'
  ],
  javascripts: [
    './www/lib/lodash/dist/lodash.js',
    './www/lib/moment/moment.js',
    './www/lib/firebase/firebase.js',
    './www/lib/ionic/js/ionic.bundle.js',
    './www/lib/raven-js/dist/raven.js',
    './www/lib/angular-resource/angular-resource.js',
    './www/lib/angular-marked/angular-marked.js',
    './www/lib/marked/lib/marked.js',
    './www/lib/angularfire/dist/angularfire.js',
    './www/lib/jquery-2.1.1.min.js',
    './www/build/js/config.js',
    './www/js/app.js',
    './www/js/controllers/**/*.js',
    './www/js/services/**/*.js'
  ]
 
};
 
gulp.task('default', ['install', 'js', 'less', 'assets', 'splash']);
 
gulp.task('js', [], function(done) {
  gulp.src(manifest.javascripts)
    .pipe(ngAnnotate())
    .pipe(concat('app.js'))
    .pipe(gulp.dest('./www/build/js'))
    .on('end', done);
});
 
gulp.task('less', ['assets'], function(done) {
  gulp.src(manifest.styles)
    .pipe(gulpif(/\.less$/, less()))
    .pipe(less())
    .pipe(prefix('last 3 versions', 'ie 9'))
    .pipe(concat('app.css'))
    .pipe(gulp.dest('./www/build/css/'))
    .on('end', done);
});

Hi friend, see my template 👯 https://github.com/jdnichollsc/Ionic-Starter-Template