This document provides information about features that were introduced in different versions of iOS and that affect the development of iOS applications. This document describes only features that affect the development of iOS applications. It does not include user-level features unless there is an aspect of the feature that affects application development. It also does not cover minor bug fixes. For additional information about a given release, you should also see the release notes.
In addition to describing the new features for each iOS release, this document attempts to provide insight as to how and when you might use those features in your own software. Wherever possible, this document also provides links to other Apple conceptual and reference documentation for that feature. For a complete list of features you can use in your iOS applications, see iOS Technology Overview.
This document includes the following articles:
“iOS 4.0” describes the new and updated features in iOS 4.0.
“iOS 3.2” describes the new and updated features in iOS 3.2.
“iOS 3.1” describes the new and updated features in iOS 3.1.
“iOS 3.0” describes the new and updated features in iOS 3.0.
Development of iOS applications requires an Intel-based Macintosh computer and an up-to-date version of Mac OS X. You must also download and install the iPhone SDK. For information about how to get the iPhone SDK, go to http://developer.apple.com/iphone/.
Last updated: 2010-07-08