On March 11, iOS 4.3 will be in the hands of iPhone, iPad and iPod touch users around the world. iOS 4.3 adds even more features to the world's most advanced mobile operating system including faster Safari mobile browsing performance with the Nitro JavaScript engine, iTunes Home Sharing, enhancements to AirPlay, and Personal Hotspot.

Submit your iOS 4.2 apps today!

OS 4.2 SDK GM seed and iOS 4.2 GM seed are now available from the iOS Dev Center. Build, test, and compile your apps with these new releases and submit them for review so they can be ready when iOS 4.2 is available to iPad, iPhone, and iPod touch users.

Learn how you can add exciting iOS 4.2 features to your apps including the capability to print directly from iPad, iPhone, and iPod touch. iPad apps can now take advantage of multitasking, Game Center, iAd, and more.

iPhone Dev Center http://developer.apple.com/iphone/

iOS SDK 4.2 beta 3 and iOS 4.2 beta 3 are now available from the iOS Dev Center. Make sure you read the Xcode 3.2.5 Readme and the iOS SDK 4.2 beta 3 Release Notes before installing these new releases.

iPhone Dev Center http://developer.apple.com/iphone/

iOS SDK 4.2 and iOS 4.2 beta 2 are now available from the iOS Dev Center. Make sure you read the Xcode 3.2.5 Readme and the iOS SDK 4.2 beta 2 Release Notes before installing these new releases.

iPhone Dev Center http://developer.apple.com/iphone/

iOS 4.1 GM seed and iOS SDK 4.1 GM seed are now available. Make sure you read the Xcode 3.2.4 Readme and the iOS SDK 4.1 GM seed Release Notes. For a wealth of information on creating Game Center games and developing for iOS 4.1, view these resources:

 

Getting Started with Game Center
Learn everything you need to know about developing your apps for Game Center, from understanding the fundamentals to updating your Game Center app once it's on the App Store.

 

 

iOS Reference Library
Read about what's new in iOS 4.1, access sample code, and review updated documentation from the iOS Reference Library.

iOS SDK and iOS 4.1 beta 3 are now available from the iPhone Dev Center. Make sure you read the Xcode 3.2.4 Readme and the iOS SDK 4.1 beta 3 Release Notes before installing and downloading these new releases.

iOS SDK and iOS 4.1 beta are now available from the iPhone Dev Center. Apps built with iOS SDK 4.1 beta should only be tested on devices running iOS 4.1. Make sure to read the Xcode 3.2.4 Readme and the iOS SDK 4.1 beta Release Notes before installing and downloading these new releases.

The next generation of the world's most advanced mobile operating system is in the hands of millions of iPhone and iPod touch users.

Make sure that your applications are compatible with iOS 4. All new applications and updates to existing applications must be built with iPhone SDK 4. In addition, the App Store will no longer support applications that target iOS 2.x.

Review the iOS 4 Readiness Checklist for a wealth of technical resources to help you make the most of the new technologies in iOS 4 and information on submitting your iOS 4 apps to the App Store.  

Since the launch of the original iPhone, Apple has made efforts to hide some of the actual tech specs of the device from consumers. Apple has never advertised or even published the processor speed or amount of RAM found in the iPhone. Arguably, Apple is trying to shield customers from these technical distractions and instead trying to focus on overall functionality.

More technically inclined customers, however, still love to know what they have to work with. The original iPhone and iPhone 3G contained 128MB of RAM, while the iPhone 3GS was boosted to 256MB of RAM. Similarly, the iPad contains 256MB of RAM. This discrepancy offers a technical explanation why Apple is not supporting iOS 4 features such as multi-tasking on the original and 3G iPhone -- there simply isn't enough RAM.

iPhone 4 Confirmed to Have 512MB of RAM (Twice the iPad and 3GS) - Mac Rumors http://www.macrumors.com/2010/06/17/iphone-4-confirmed-to-have-512mb-of-ram-twice-the-ipad-and-3gs/

Submit your iOS 4 apps for review so they can be ready for sale when iOS 4 is available to iPhone and iPod touch users. Make sure you have built and tested your applications using iOS 4 and iPhone SDK 4 GM seed, which you can download from the iPhone Dev Center.