Some users love the user interface changes in watchOS 10. Others do not. What changed, and how does Apple decide to update a perfectly good user interface, anyway? Former Apple engineer David Shayer explains what Apple changed and likely why, before sharing how Apple approaches major interface changes.

Chatbots have just progressed to the next level with OpenAI’s release of ChatGPT. Programmer David Shayer explains what’s behind ChatGPT’s curtain and ponders how we’ll deal with AI-driven chatbots that sound confident and reasonable but may be entirely wrong.

Since the Apple Watch debuted, users and developers have wanted third-party watch faces. Sorry, but they’re not coming. Former Apple Watch engineer David Shayer explains why.

15 years ago, Apple helped the US government develop a custom iPod for clandestine missions. Of course, neither Apple nor the US government will admit this ever happened. Former Apple engineer and inadvertent intelligence operative David Shayer tells the story of the iPod that never existed.

Apple’s new Security Research Device Program provides security researchers with special iPhones to help them find vulnerabilities in iOS for Apple. Former Apple engineer David Shayer examines how Apple might be tweaking iPhone hardware to make this work.

You undoubtedly know about Apple’s version numbering scheme for its operating systems—iOS 13.5.1 and macOS 10.15.5, for instance. But did you know Apple also has a hidden build numbering scheme that can be even more useful? Former Apple engineer David Shayer explains how to decode build numbers and learn from them.

With another WWDC behind us, that means it's beta season, with new versions of macOS, iOS, watchOS, and tvOS for developers brave enough to test them. Former Apple engineer David Shayer explains what you need to do to increase the chances that Apple will fix the bugs you report.

Rumors of ARM-based Macs continue to appear. Lower power and longer battery life are always cited. But even more important are the business advantages Apple would reap from switching from Intel to ARM. Former Apple engineer David Shayer explains what would be behind such a processor transition.

David Shayer, who has worked as a software engineer at Apple and other companies, explains Apple’s internal approach to privacy and contrasts it with other companies, all with an eye toward showing why we should trust the current draft of the COVID-19 exposure notification proposal from Apple and Google.

By most accounts, the release of iOS 13 and macOS 10.15 Catalina have been troubled, with numerous significant bugs making it past Apple’s internal testing and the public beta phase. Former Apple engineer David Shayer explains the underlying reasons these releases have had so many problems.

A few months ago in TidBITS I compared the various disk repair programs then available for Mac OS X: Norton Utilities 8.0 ($100), DiskWarrior 3.0 ($80), Drive 10 1.1.4 ($70), Disk Guardian 2.2 ($70), and Apple's Disk Utility (free)

Some things are inevitable. Death, taxes, and disk crashes. One day you will try to open an important file, only to receive a dire error message. Or perhaps you'll discover that an entire folder has vanished

Optimizing disks is a waste of time. There, I said it. The horse is out of the bag, the cat is out of the barn. So why do so many people believe that an optimizer is an essential part of any Mac user's tool kit? And what does it mean to optimize a disk, anyway? Background Fragments -- When you save a file to disk, the file system looks for an empty space to write the data