Many thanks for this exceptional book. I really love the performance and the small footprint of SpriteKit and that is why I still use it whenever possible.
Yes thanks for putting out the book! Even if I do use unity later on SpriteKit is a great jumping off point for game development … its ui is a lot less clunky and gray than unity ! I’ll follow separate threads in this.
For augmented reality SpriteKit has a big advantage over unity in that you can just paste the sk classes into SceneKit and work natively in augmented reality. But unity looks great too!
Very Sorry to hear that 
RW was the BEST site for learning iOS dev. Hope you guys change your mind and maybe author a new book.