The following reading material will provide you with more information about Ionic, Firebase, ngx-formly, and Ionic Native:
- Ionic Framework documentation: https://ionicframework.com/docs.
- AngularFire: https://github.com/angular/angularfire2.
- ngx-formly documentation: https://ngx-formly.github.io/ngx-formly/.
- Ionic Native documentation: https://ionicframework.com/docs/native.