So, the documentation for the MacOs (v220.127.116.11193.0321) desktop release asks you to set the constants:
… in the file appDelegate.m
Now, the file appDelegate.m does not exist and the visual in the documentation does not match the file SDKAppDelegate.m - the closest match in the project directory.
Adding the constants in that file appears to make no difference - one is prompted for all those values when the app starts.
Further, a scan of the source code reveals no reference to the values kZoomSDKAppKey or kZoomSDKAppSecret
I am a noob but, exactly for this reason, having documentation which matches the supplied SDK so poorly is profoundly unhelpful.