I'm trying to install a simple ARKit app, made in Unity using this tutorial, but when I'm opening it in XCode 9 I see this error:
I choosed my iPhone as a target device, but the result is the same.
I use:
Xcode 9 Beta
Iphone SE, public IOS 11
I registered to Apple Developer here (for free): https://developer.apple.com/
Why is this happening and how can I fix that?
I had the same problem as you. I figured out by change the field of bundle identifier (the second field in your picture) from the default to something different, and refresh the signing status.