This is the Swift playgrounds book for which Apple awarded me a WWDC19 Scholarship.
The reader follows the journey of the fish Finley, who leads a comfortable life, but still feels like he is missing something. When he hears about a thing called the "ocean" he decides to embark on a journey to see it, although he fears the dangers and uncertainty along the way. During his travels he meets new friends who help him overcome obstacles until he finally reaches his goal. It is then, when he realizes that his initial fears were not necessary and meeting new friends along the way was the actual goal of the journey.
Main technology used was SpriteKit. Also, the fish swarming behavior is modeled after the real world behavior of fish.
To try it out for yourself, click here to download (iPad with installed Swift Playgrounds app required)
Alternatively, a video about the submission can be found here: https://youtu.be/CPZWncZcA94