Windows

Windows is an operating system first released by Microsoft on 1985, representing the primary competition to macOS.

Many programs have been released for Windows by Apple. The first major software was QuickTime for Windows, released in 1992 for Windows 3.1. Later, the 2003 release of iTunes for Windows opened the iTunes Store and iPod to the much larger market of Windows users. With the release of Intel Macs in 2006, Apple provided Boot Camp as a utility to install drivers and other tools useful to running Windows on a Mac. Between 2007 and 2012, Safari was made available for Windows.

Since 2019, Apple has been transitioning Windows software distributions from classic desktop releases, to .appx packages released on the Microsoft Store. iCloud for Windows has transitioned to being distributed only via the Microsoft Store, while iTunes continues to provide both classic and Microsoft Store distributions. The app is identical in both cases - it is only packaged differently. Apple's classic app releases are maintained by Apple Software Update, while the Microsoft Store apps are updated by Windows itself.

The Apple Devices, Apple Music, and Apple TV apps make use of the Windows Runtime (WinRT) and Windows UI Library (WinUI), while older apps such as iTunes, Safari, and QuickTime use the traditional Windows API (Win32). In both cases, Apple's current Windows apps partially or fully make use of ports of the Objective-C runtime and frameworks such as CoreFoundation, AppKit, WebKit, and MobileDevice.