Jonathan Zdziarski, the author of O’Reilly’s iPhone Open Application Development, spoke about writing applications for the iPhone–both on jailbroken phones and via the official Apple SDK–at the Cambridge, MA Apple Store! Wade Roush reports on the event:

But the really amazing thing about the event was that Apple even let the keynote speaker, Jonathan Zdziarski, in the front door. Zdziarski was one of the first software engineers to figure out how to hack the iPhone, and he’s the author of a forthcoming O’Reilly Media book called iPhone Open Application Development, which gives readers explicit instructions on jail-breaking iPhones (that is, bypassing Apple’s restrictions on loading third-party software). So for Apple to give Zdziarski the podium at an Apple retail location is a little like Steve Ballmer inviting Linus Torvalds to speak at a Windows product launch.

Wade Roush: Jail-Breaking iPhones and Other Tales from the Apple Store.

FROM O’Reilly – iPhone Open Application Development – In this clear and concise book, Jonathan Zdziarski — one of the original hackers of the iPhone — explains how developers can design third-party software that will run on this device. You’ll learn about the open SDK for the iPhone developed by the community, the Objective-C language it uses, and background on the operating system. You also get detailed recipes and working examples for several iPhone features.