Loading popup animation does not work on iPhone

This is the screenshot of the issue - the spinner animation does not work as expected, instead of spinning effect there is just one line blinking:

To reproduce:
1 - initialise a new Ionic project: ionic start myProject --v2
2 - in pages/home/home.html add:

<button (click)="testLoader()">testLoader</button>

3 - Complete pages/home/home.ts:

import {Component} from '@angular/core';
import {NavController, LoadingController} from 'ionic-angular';

  templateUrl: 'build/pages/home/home.html'
export class HomePage {
  constructor(private navCtrl: NavController, private loading: LoadingController) {

  testLoader() {
    var loader = this.loading.create({content: 'Please wait...'});

4 - start serving the app, open it on iPhone or iPhone simulator (I tried iPhone6/5, iOS 8.2) and click testLoader button on the home page (one way to get an external url to be able to open it on a simulator is to use ngrok: https://ngrok.com/docs/2#getting-started)