I am working through Catnap and have ground to a halt because can’t find the SKUtils folder. I just re-downloaded the book, but I am not able to find SKTUtils. i am guessing the rest of the tutorial relies on the library of SKTUtils functions.
Have a look in some of the later chapter start or final folders.
Or you can download it from github: https://github.com/raywenderlich/SKTUtils