Unity iOS: blackout on both left and right side in google cardboard view.

Summary:
I am following guide for Unity-iOS from here. I am having issues with "HelloVR" demo scene that comes with sdk unity package.

I have two issues here.

1. After installing game on IPhone 5S, without cardboard, both left and right views are not symmetric. Right view/lens shows more towards left side and Left view/lens shows more towards right side. [Attached image gvr_1.jpg]
   
   
   
2. When using Cardboard views, i see left and right side as completely black and only middle rectangular part for game [Attached vr_camera_error2.jpg]
   

Found using:

• Google VR SDK version: v1.130.1
• Unity version: 2017.3.1f1
• Phone manufacturer, model, and O/S version: IPhone 5S, Model:MF352HN/A, OS version:11.2.2 (15C202)
• Viewer manufacturer & model: Google v2.0

Steps to reproduce the issue:

1. On Unity 2017.3.1f1, follow guided for "HelloVR" demo Scene VR.
2. Switch platform to iOS, set VR settings on "Player Settings" and create iOS build.

Edit#1: Found Issue#2 is specific to iOS. Output from cardboard viewer with Android device is working fine. With android device i can see the whole scene and not blackout on both left-right sides.

 

1. It is normal for the view to be asymmetric: The field of view depends on how your phone sits in the viewer and are computed from the phone size relative to the lenses in the viewer.

2. Did not see this issue on my 6S.

 

Your example images looks extremely cross-eyed to me. Haven't noticed that my self.
Is it how it looks in the phone, have you calibrated the Cardboard headset for your phone?