The Third Party
This simple app use RxSwift module. So if you have no installed CocoaPods before, you had to install it.
CocoaPods is a dependency manager for Cocoa projects. You can install it with the following command:
$ gem install cocoapods
To integrate RxSwift into this Xcode project using CocoaPods, specify it in your Podfile:
platform :ios, '10.0' use_frameworks! target '<Your Target Name>' do pod 'RxSwift' end
Then, run the following command:
$ pod install
This app use Parse server to save and load user info.
Sign in and up both will save user in UserDefault because AppDelegate class will check which page user should go if the app dosn't exist in backend.
To see more detail in source code.