app.js

angular.module('starter', ['ionic'])
.run(["LocationService", async LocationService => {
    const coords = await LocationService.getPosition();

    console.log(coords);
}])
.service("LocationService", ["$window", "$q", ($window, $q) => (
    {
        getPosition() {
            const dfd = $q.defer();
            $window.navigator.geolocation.getCurrentPosition(dfd.resolve, dfd.reject);
            return dfd.promise;
        }
    }
)]);

gulpfile.js

const gulp = require('gulp');
const concat = require('gulp-concat');
const babel = require("gulp-babel");

const paths = {
  js: ['./www/app/**/*.js'],
};

gulp.task('default', ['babel']);

gulp.task('babel', () =>
    gulp.src(paths.js)
        .pipe(babel({
            presets: ['es2015'],
            plugins: ['transform-async-to-generator', 'transform-regenerator'],
        }))
        .pipe(concat('app.min.js'))
        .pipe(gulp.dest('./www/dist/'))
);

package.json

{
  "name": "foo",
  "version": "1.1.1",
  "description": "foo: An Ionic project",
  "devDependencies": {
    "babel-plugin-transform-async-to-generator": "^6.8.0",
    "babel-plugin-transform-regenerator": "^6.9.0",
    "babel-preset-es2015": "^6.9.0",
    "bower": "^1.3.3",
    "gulp": "^3.5.6",
    "gulp-babel": "^6.1.2",
    "gulp-concat": "^2.6.0"
  },
  "cordovaPlugins": [
    "cordova-plugin-device",
    "cordova-plugin-console",
    "cordova-plugin-whitelist",
    "cordova-plugin-splashscreen",
    "cordova-plugin-statusbar",
    "ionic-plugin-keyboard"
  ],
  "cordovaPlatforms": []
}