It's objective-c and spritekit. I started making games back in 2009 using objective-c and uikit. Honestly, once you get those sprites moving on the screen I find that it really doesn't matter what you're using, but Spritekit is awesome.

I'm pretty good with Xamarin in c# development. I use that mainly for business apps, but nothing beats objective-c and the opensource projects out there to make iOS apps.

Thanks man