This article summarizes the developer-related features introduced in iOS 4.1. This version of the operating system runs on iPhone and iPod touch only and does not run on iPad. In addition to describing the new features, this article lists the documents that describe those features in more detail.
For the latest updates and information, you should also see iOS 4.1 Release Notes. For the list of API differences between the iOS 4.1 and earlier versions of iOS, see iOS 4.1 API Diffs.
Game Center is an extension to the Game Kit framework that provides support for the following features:
Aliases allow users to create their own online persona. Users log in to Game Center and interact with other players anonymously through their alias. Players can set status messages as well as mark specific people as their friends.
Leaderboards allow your application to post user scores to Game Center and retrieve them later. You might use this feature to show the best scores among all users of your application.
Matchmaking allows you to create multiplayer games by connecting players who are logged into Game Center. Players do not have to be local to each other to join a multiplayer game.
Achievements allows you to record the progress a player has made in your game.
The preceding features all contribute towards the experience users see in the Game Center application. For information about the classes of the Game Kit framework, see Game Kit Framework Reference.
The following existing frameworks and technologies include additional incremental changes. For a complete list of new interfaces, see iOS 4.1 API Diffs.
The AV Foundation framework includes the following enhancements:
AVAssetReaderclass for reading samples from media files.
AVAssetWriterclass for writing samples to a data file and optionally compressing them.
For more information about the classes of the AV Foundation framework, see AV Foundation Framework Reference.
The Assets Library framework includes new methods to save images to a user’s photo album. These new methods are declared in the
The Core Text framework includes new functions for managing fonts. For more information about the functions available in the Core Text framework, see Core Text Reference Collection.
The System Configuration framework contains new interfaces for identifying captive networks. For more information about the functions available in the System Configuration framework, see System Configuration Framework Reference.
The UIKit framework includes the following enhancements:
Additional constants for the
UIImagePickerControllerclass that allow you to obtain additional information about an image.
A decimal keyboard type that you can use for text entry. You can specify this keyboard type using the
For more information about the classes of the UIKit framework, see UIKit Framework Reference.