14Saving, Loading, and Application States

There are many ways to save and load data in an iOS application. This chapter will take you through some of the most common mechanisms as well as the concepts you need to understand to write to or read from the filesystem on iOS.


Any iOS application is really doing one thing: providing an interface for a user to manipulate data. Every object in an application has a role in this process. Model objects, as you know, are responsible for holding on to the data that the user manipulates. View objects simply reflect that data, and controllers are responsible for what is going on while the application is running. Therefore, when talking about saving and loading data, we are almost always talking about ...

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