These files, residing on macOS, represent software components designed for Apple’s mobile operating system. They can encompass a range of items, including application installers (IPA files), firmware updates (IPSW files), disk images (DMG files), and support files used by iTunes or Finder when interacting with iPhones, iPads, and iPod Touches. For example, an IPSW file is used to restore or update the operating system on an iPhone through Finder (formerly iTunes).
The presence of these files on a Mac is crucial for several reasons. They enable users to back up and restore their mobile devices, install applications not available through the App Store (through methods like sideloading), and perform operating system updates. Historically, iTunes was the primary means of managing these files; however, recent macOS versions have shifted this functionality to Finder, streamlining the user experience. Understanding their function allows for greater control over Apple mobile devices and their associated data.