Apple has recently launched SDK for iPhone 3.0 OS  and 3.1 Beta app developers. With over 1,000 new APIs, iPhone SDK provides developers with a range of new possibilities to enhance the functionality of their applications. New APIs also provide support for applications to communicate with hardware accessories attached to iPhone or iPod touch.

The previous Version of iPhone SDK was a huge success ,which almost over 250,000 downloads,since its launch on March 6.

Download new iPhone SDK (2.08 GB)

The iPhone 3.0 SDK includes new features to take advantage of the unique capabilities of iPhone 3GS including:

Open GL ES 2.0:Games and other graphics-intensive applications can now take advantage of OpenGL ES 2.0, the latest version of the standard for hardware-accelerated graphics designed for mobile devices. OpenGL ES 2.0 adds programmable shaders that give you more control over the look of your scenes, allowing you to create more complex renderings and spectacular visual effects.
Accessibility:Make your applications accessible to everyone—even those with impaired vision. New to iPhone OS 3.0, VoiceOver helps users navigate through your application by translating standard gestures and providing spoken descriptions you include. Using the updated developer tools, you can easily adapt your iPhone applications to work with VoiceOver.
Video Recording:Embed a video recorder into your application using the new interface used in the Camera application. The new interface provides a switch to toggle between still photos and video mode, giving your users the flexibility to capture the moment the way they want. Once the video has been captured, users can choose the videos they want from the updated Media Picker.
Compass:Add heading information to your location-aware application. Core Location has been updated to allow your applications to track which direction the user is facing using iPhone 3GS’s built-in digital compass. While incredibly useful for any navigation-based application, when combined with the accelerometer the compass can also be used to capture iPhone’s true orientation.
check out the Apple indtroductory video on SDK

Official information by Apple

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