iOS 4 is the next generation of the world’s most innovative mobile operating system. Its unique capabilities and new technologies will change what’s possible on a mobile platform

iPhone SDK 4 GM seed

With a rich set of over 1500 new APIs, iPhone SDK for iOS 4 provides you with an amazing range of technologies to enhance the functionality of your iPhone and iPod touch apps. iPhone Developer Program members can visit the iPhone Dev Center to download the iPhone SDK 4 GM seed now.


iOS 4 delivers seven new multitasking services that allow your apps to perform tasks in the background while preserving battery life and performance. These multitasking services include:

  • Background audio – Allows your app to play audio continuously. So customers can listen to your app while they surf the web, play games, and more.
  • Voice over IP – Your VoIP apps can now be even better. Users can now receive VoIP calls and have conversations while using another app. Your users can even receive calls when their phones are locked in their pocket.
  • Background location – Navigation apps can now continue to guide users who are listening to their iPods, or using other apps. iOS 4 also provides a new and battery efficient way to monitor location when users move between cell towers. This is a great way for your social networking apps to keep track of users and their friends’ locations.
  • Push notifications – Receive alerts from your remote servers even when your app isn’t running.
  • Local notifications – Your app can now alert users of scheduled events and alarms in the background, no servers required.
  • Task finishing – If your app is in mid-task when your customer leaves it, the app can now keep running to finish the task.
  • Fast app switching – All developers should take advantage of this. This will allow users to leave your app and come right back to where they were when they left – no more having to reload the app



Apple’s new mobile advertising platform, combines the emotion of TV ads with the interactivity of web ads. When users click on mobile ads they are almost always taken out of their app to a web browser, which loads the advertiser’s webpage. Users must then navigate back to their app, and it is often difficult or impossible to return to exactly where they left. iAd solves this problem by displaying full-screen video and interactive ad content without ever leaving the app, and letting users return to their app anytime they choose. iPhone SDK 4 for iOS 4 lets developers easily embed iAd opportunities within their apps, and the ads are dynamically and wirelessly delivered to the device. Apple will sell and serve the ads, and developers will receive 60 percent of iAd revenue.

Game Center

The iOS 4 GM seed software and SDK includes a developer preview of the GameKit APIs that allows you to create apps that will work with Game Center, Apple’s new social gaming network. Your users can invite friends to play a game, start a multiplayer game through matchmaking, track their achievements, and compare their high scores on a leader board. The APIs are available to you now and Game Center will be available to iPhone and iPod touch users later this year.

New APIs

iPhone SDK 4 contains over 1500 new APIs to incorporate into your iPhone and iPod touch apps, including:

Calendar Access

Apps can now create and edit events directly in the Calendar app with Event Kit. Create recurring events, set up start and end times and assign them to any calendar on the device.

In-App SMS

Compose SMS messages from within apps, similar to the Mail compose sheet added in iPhone SDK 3.0.

Photo Library Access

Applications now have direct access to user photos and videos with the Media Library APIs.

Video playback & Capture

You now have full programmatic control over video playback and capture, using new APIs in the AV Foundation framework.

Map Kit Improvements

Mapping applications can now include overlays that can identify regions on a map. Draw routes with annotations for customized directions and other functionalities.

Quick Look

Applications can now present previews of documents, like attachments in Mail, using the new Quick Look APIs.


Accelerate provides hundreds of mathematical functions optimized for iPhone and iPod touch, including signal-processing routines, fast Fourier transforms, basic vector and matrix operations, and industry-standard functions for factoring matrices and solving systems of linear equations.

New in Tools

With a wealth of new tools and refinements throughout the suite of current tools, you’ll find that developing amazing iPhone and iPod touch apps is easier than ever before.

Automated testing

Automate the testing of your application by scripting touch events using the new UIAutomation Instrument.

Performance and power analysis

Collect finely-grained performance data and track the power usage of your application using the new Time Profiler and Energy Diagnostics Instruments for iPhone OS.

iOS 4 Compatibility

iOS 4 will work with iPhone 3G and iPhone 3GS. Support for the second and third-generation iPod touch will be available this summer, iPad support will be available in the fall. Not all features are compatible with all devices. For example, multitasking is available only with iPhone 3GS and the third-generation iPod touch (32GB and 64GB models from late 2009).