Return value from a promise in Angular

I am a little bit confused with Promises. I have the following provider in Ionic + Angular:

@Injectable()
export class StorageProvider { 

  constructor( public storage:Storage ) {}

  save(keyname: string, data: any): Promise<any> {
    return this.storage.set(keyname, data);
  }

  retrieve(keyname: string): Promise<any> {
    return this.storage.get(keyname);
  }

  clear(): Promise<void> {
    return this.storage.clear();
  }

  delete(keyname): Promise<any> {
    return this.storage.remove(keyname);
  }

  isLogged() {
      return this.retrieve('user').then( value => { value ? true : false });
  }

}

And in one of my components:

console.log(this.storage.isLogged()); 

The problem is that it returns the promise object and not true or false

If I change my component to:

this.storage.isLogged().then(function(data) { console.log(data)});

Then I get an output of undefined