The iOS store is perhaps the most restrictive and complicated of all the mobile app stores to submit an app to. It also has more exhaustive submission guidelines, such as: it should not replicate the functionality of native applications. The process to get to the point of submitting an app is also more complicated.
Deployment for iOS
The package
Qt Creator comes with support for creating and signing iOS packages. As with Android, you will need certificates from your developer account. This is what you see when you log into the developer account at Apple:
Once in your developer account, click on the icon labelled Certificates, Identifiers & Profiles to add certificates. Notice the list under Certificates...