here below, 10 important points for a good maintanaince of your Xcode project
NO HardCoded (value hammereds in code, for example: if(x==-5))
divide images into xcassets (to manage all resolution and so as to have separate folders)
use patterns (Singleton, MVC, Facade, etc... as far as possible, in this way your code will be cleaner)
file of constants in .pch file header (main color, return value of some service, etc...)
create Helper/Utility Class to reuse in all projects
create .plist file or new Targets for configuration (for example: url of services(integration, production environment))
comment your code in particular for captious algorithm
divide in Multiple storyboards (design not more than 10 view-controllers in a single storyboard)
create Localizable.strings file for your message (in all languages)
Use gitflow for branching ()
