Upgrading to cordova iOS version 3.9.2 was the solution for me. I was on 3.8.0 somehow.
ionic platform remove ios
ionic platform add firstname.lastname@example.org
ionic prepare ios
You could use cordova iOS v4.1.0 as well, but you lose support for iOS 6 and 7. Plus cordova-plugin-screen-orientation is not updated for v4, so you have to lock your app to portrait or landscape. Otherwise, 4.1.0 seems good to go!