ios publishing costs?

If I were to publish a game to ios, would I only have to pay for Xamarin.ios licence, or would I also have to pay for the ios sdk licence? Also are there any other publishing costs that I should be aware of?

The “ios sdk licence” is your ticket to the App Store. You don’t need anything else other than that and the Xamarin license. The total cost is $400 (or $200 if you are a student) per year.