// component
onClick(record){
  this.myService.updateRecord(params).subscribe();
}

// service
updateRecord(record){
  return new Observable((observer) => {
    Observable.forkJoin(
      Observable.fromPromise(this.storage.get('things')),
      Observable.fromPromise(this.storage.get('other_things'))
    ).subscribe(
      (results) => {
        let things = results[0] || []
        let other_things = results[1] || []

        // do stuffs

        observer.next([record])
        observer.complete()
      })
  })
}