This chapter showed us, by exploiting the power of Xcode and Swift, we can create fully working app.
Depending on your level of iOS knowledge, you could have found this app either too hard or to simple to understand; for the former, don't loose your enthusiasm, read the code again, and try to execute the app adding few strategically placed print() instructions in the code to see the content of the various variables; for the latter's, I hope you have found at least some tricks you can start to use right now.
Of course, simply after reading this chapter, nobody can be considered an expert in Swift and Xcode. However, the information here is enough to let you understand all of the code we'll be using in the upcoming chapters to build several kinds of other interesting apps.
In the next chapter, we'll continue to explore Swift and iOS by implementing another game, a memory game that will let us make use of the power of structs. You will also learn about some new things in UIKit.