TL;DR use Xcode to open Unity-iPhone.xcworkspace not Unity-iPhone.xcodeproj
While following this guide for building apps for iphones
I came across an error after I activated the PlayerSetting>iOS>Virtual Reality SDK + Cardboard
mach-o linker (id) error
after I did some searching I found
>I finally found out that i had to open the xcworkspace instead of the xcodeproj. Using the xcworkspace, there is a “Pods” that is added and compiled before the unity project.
If this is the solution for building an iOS build it would be nice to mention somewhere to use the xcworkspace instead of xcodeproj.