The duplicate “Native phone” profiles that are shown in the “Add Navigation Profile” screen are caused by a bug and will not work, so please do not use these profiles. The other profiles are valid and will work as expected. This issue will be fixed in the next release (7.22.2).
The only thing i could find about this in de the documentation is this:
There is a small breaking API change where the property
navigation.NavigationDocument.profiles is now of a different type to accommodate the introduction of native navigation profiles. For Mendix version 7.21.0 and earlier, these profiles can be safely casted to
navigation.NavigationProfile. In Mendix version 7.22.0 and later, there can also be instances of
navigation.NativeNavigationProfile in this property.
Check out the release notes from the model SDK: https://docs.mendix.com/releasenotes/sdk/model-sdk-4
I think this is why it is there