When I am submitting the app for the Apple App Store, does it matter which device I archive it as? My app is universal and I currently archived it on my iPhone and my iPad. Do I have to submit both archives? Or can I choose either one?
You do not have to specify device type while archiving (it will archive to the same location in the Organizer->Archives tab anyway). If you have all the proper configuration set and screenshots/meta data correct then Apple will take care of it. They will put it on the app store and let only those who can buy it (according to your settings) see it.