This chapter was shorter than most of the other chapters in this book. Nevertheless, we finished building the Cube Runner game by adding a proper game-over features, explosions, and a vibration in the case of a crash with a cube. We set up Game Center to collect the scores.
Although the game is pretty entertaining, there's always room for improvement; for example, different lanes could easily be added, or you could use different building functions for every section. You might even want to change the texture and shape of the cube to create planets. A bullet shooting from the jet could be added to wipe out small cubes inside the lanes.
However, adding these enhancements could be challenging. Nevertheless, by now you must have a good amount of knowledge of Swift and its frameworks well enough to start developing iOS apps in Swift on your own.