Ngx-translate and Ionic 3?

1. Your code looks good. May only guess is maybe trying to move your initialization part from app.component constructor to app.component ngAfterViewInit for example ? A wild guess is that maybe this.storage isn't yet initialized when you try to access it in your app.component contructor and therefore the default language couldn't be set?

2. If I doesn't miss it I've to feeling you are not telling ngx-translate which language should be use. You set a default language but doesn't set the one to use. I would add this.translateService.use(...);

3. Also it's possible to guess the language without the storage, so I would do something like

   ngAfterViewInit() {
      let userLang = navigator.language.split('-')[0];
     userLang = /(hi)/gi.test(userLang) ? userLang : 'en';
   
   this.translateService.setDefaultLang('en');
   this.translateService.use(userLang);
   
   this.storage.get('AppLangcode')
     .then((AppLangcode) => {
       if(AppLangcode==null){
          this.translateService.use(userLang);
       }else{
          this.translateService.use(AppLangcode);
       }
     });
   }

Not sure it will work but maybe i will give you some ideas?