Welcome to objc.io issue #4!

In this issue we are taking an in-depth look into Apple's model layer framework, Core Data.

Core Data is a powerful object graph management and persistence framework, which has been available on both iOS and OS X for many years. Nevertheless, even experienced developers often don't use it. Additionally, there is a lot of misleading information about Core Data on the Internet, which can confuse newcomers.

The articles in this issue provide a deeper overview of what Core Data is, how it works, and how you should use it. If you haven't worked with Core Data before, you will find the overview and the example of building a full Core Data application useful. If you're familiar with Core Data, we have several articles which cover the topics of managed objects, fetching data, importing large data sets, and migrations (the latter is thanks to our guest writer Martin Hwasser).

Last but not least, special guest writer Brent Simmons gives you an overview of how he uses SQLite directly in his applications, including the recently released Vesper, but why you probably shouldn't. It's an interesting peek behind the scenes that shows what it takes to manually recreate what Core Data does for us.

We wish you a successful iOS 7 launch month!

All the best from Berlin,

Chris, Daniel, and Florian.