Change default ion-navbar "back" button ios

[ondonda]

@App({
  template: '<ion-nav [root]="rootPage"></ion-nav>',
  config: {
    platforms: {
   ios: {
     backButtonText: 'text',
     }
   }
 } // http://ionicframework.com/docs/v2/api/config/Config/
})

if you want to target a specific platform