For development purposes, it's good to get an understanding of how long an app takes to build. XCode has this hidden feature that will display how long it takes to run a specific build. Overtime, you can take a look at this number and try to decrease it via different build settings or modularizing your code.
Paste this into Terminal:
defaults write com.apple.dt.Xcode ShowBuildOperationDuration -bool YES
Now in Xcode, you will see how long it takes to build: