Before performing source code review, you should get some hands-on experience with developing an iOS application. In this post, I will show you some of the possible steps to get started. You will spend roughly 30 hours on developing some iOS applications and learning some of the common libraries in Swift 5.
Initial Readings – 6 hours
Read App Development with Swift
Build a Simple iOS application – 4 hours
Now it is time to write some code. The purpose of this exercise is to understand the basic structure of an iOS application such as:
– Learn how to link UI objects (e.g. UIImage, Buttons, Sliders etc.) in the Main Board to the View Controller
– Learn how the function in the ViewController can update the UI objects values.
– Naming UI objects
– Uploading images into Assets.xcassets directory
– Learn to initialise variables in Swift.
– Differentiate between ‘var’ and ‘let’ declaration (var is used to initialise the mutables while let is used for declaring constant)

Build an intermediate iOS application – 8 hours
Build an application which stores data locally. The types of data should also include sensitive data such as username and password.
Purpose of UserDefaults. The data is saved as plist. This is not a database. Just use it to learn small kb of data and not for large amount of data.
Data Storage Methods:
1. UserDefaults
2. Encode Data into plists
3. Keychain (An API to store sensitive data (e.g. username, password etc.) securely
4. SQLite
5. Core Data (Object Oriented Database)
6. Realm
Build another intermediate iOS application – 12 hours
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