Use UIBlurEffect for blur

[Jordi Puigdellívol]

    self.blurView = [[UIVisualEffectView alloc] initWithEffect:blurEffect];
    self.blurView.frame = self.parentVc.view.bounds;
    self.blurView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
    [self.parentVc.view addSubview:self.blurView];