Technical question here, since it's not open source. Do you use only UIKit components (like UIView with UIKitDynamics) or are you using SpriteKit/Coco2D? I'm

Technical question here, since it's not open source. Do you use only UIKit components (like UIView with UIKitDynamics) or are you using SpriteKit/Coco2D? I'm impressed with the quality of your app/game, I'll be even more impressed if you don't use any game related libraries.