import { NgModule } from '@angular/core';
  import { DeviceDetectorModule } from 'ngx-device-detector';
  ...
  @NgModule({
    declarations: [
      ...
      LoginComponent,
      SignupComponent
      ...
    ],
    imports: [
      CommonModule,
      FormsModule,
      DeviceDetectorModule.forRoot()
    ],
    providers:[
      AuthService
    ]
    ...
  })

  import { Component } from '@angular/core';
  ...
  import { DeviceDetectorService } from 'ngx-device-detector';
  ...
  @Component({
    selector: 'home',  // <home></home>
    styleUrls: [ './home.component.scss' ],
    templateUrl: './home.component.html',
    ...
  })

  export class HomeComponent {
    deviceInfo = null;
    ...
    constructor(..., private http: Http, private deviceService: DeviceDetectorService) {
      this.epicFunction();
    }
    ...
    epicFunction() {
      console.log('hello `Home` component');
      this.deviceInfo = this.deviceService.getDeviceInfo();
      const isMobile = this.deviceService.isMobile();
      const isTablet = this.deviceService.isTablet();
      const isDesktopDevice = this.deviceService.isDesktop();
      console.log(this.deviceInfo);
      console.log(isMobile);  // returns if the device is a mobile device (android / iPhone / windows-phone etc)
      console.log(isTablet);  // returns if the device us a tablet (iPad etc)
      console.log(isDesktopDevice); // returns if the app is running on a Desktop browser.
    }
    ...
  }

import 'core-js/es6/string';
import 'core-js/es6/array';
import 'core-js/es6/map';