Hey guys,
I am very new in Ionic and I am trying to understand how this all works around.
I am trying to do an app with firebase authentication using angularfire2 (actually the important thing here is that I am trying to import a provider)
In a lot of tutorials, I always see that people uses @NgModule in app.module.ts file to import everything they want to.
For example, I’ve found this:
@NgModule({
declarations: [
MyApp,
HomePage
],
imports: [
IonicModule.forRoot(MyApp),
AngularFireModule.initializeApp(firebaseConfig)
],
bootstrap: [IonicApp],
entryComponents: [
MyApp,
HomePage
],
providers: [
{provide: ErrorHandler, useClass: IonicErrorHandler}
]
})
I really need to use it? Because I have created a new ionic app and I dont even found app.module.ts file.
All I have is a app.ts file and in the end of the file I have
ionicBootstrap(MyApp)
And I have read that I can pass my providers like:
ionicBootstrap(MyApp, [MyProvider], {});
Is this possible instead of using @ngModule annotation?
And I also have read that instead of using ionicBoostrap we should import any provider in a top level component (I think it could be the component in app.ts file) , because doing it we would be able to use this provider any time in any component.
So, it should be something like this:
@Component({
templateUrl: 'build/myApp.html',
directives: [...],
providers: [..., MyProvider]
})
class MyApp{
// ...
}
As you can see Iam really lost 
What is the best way?
1-Using @ngModule
2-Using ionicBootstrap
3-Importing in the provider in a top level component
And, what app.module.ts file is used for? Can I use app.ts to do all the job?
Does anybody has a documentation about theses things?
Thanks a lot 