Apple announces that iPhone Software Development Kit (SDK) will be made available sometimes in February 2008. It is not clear if the SDK will be Mac OS X only or will be available for Windows OS also.
From Apple Hot News:
Third Party Applications on the iPhone
Let me just say it: We want native third party applications on the iPhone, and we plan to have an SDK in developers’ hands in February. …….It will take until February to release an SDK because we’re trying to do two diametrically opposed things at once—provide an advanced and open platform to developers while at the same time protect iPhone users from viruses, malware, privacy attacks, etc. …….
……. We are working on an advanced system which will offer developers broad access to natively program the iPhone’s amazing software platform while at the same time protecting users from malicious programs.
We think a few months of patience now will be rewarded by many years of great third party applications running on safe and reliable iPhones.
Steve
P.S.: The SDK will also allow developers to create applications for iPod touch. [Oct 17, 2007]
Back in July 2002, on TWiT 103 Leo Laporte mentioned a rumor he heard about the iPhone SDK. According to Laporte, he heard that Apple already had a “mature” iPhone SDK on Mac OS X, and Apple was still working on the SDK on Windows OS. It was immediately called “bogus”. Apparently Laporte received this info on his “The Tech Guy Radio Show” chat room from an anonymous person. Unfortunately, Laporte no longer posts any of the chat transcript to quote the info verbatim. In effect, the anonymous person told Laporte that Apple had a working iPhone SDK on Mac OS X and might be working on the Windows OS version. Despite of all conflicting news, the information is somewhat accurate.
The iPhone and iPod touch OS is based on Mac OS X 10.5 Leopard. Most likely that the SDK will require Leopard, and there will be no Windows OS version. This means if you want to develop apps for the iPhone and iPod touch, you need to use Mac OS X Leopard.