Apple Watch, HomePod and most Apple TV models update over the air. The OTA files listed here are the official update packages, useful for archiving and repair research. Normal users install them through Apple’s own update menus, not by hand.

How to update normally

Apple Watch: on the paired iPhone open the Watch app → General → Software Update. Keep the watch on its charger, at 50% or more, near the iPhone.
HomePod: on iPhone or iPad open the Home app → Home Settings → Software Update.
Apple TV: Settings → System → Software Updates.
Vision Pro: Settings → General → Software Update.

Restoring a device that won’t start

Apple Watch cannot be restored from a computer by users. If it shows a red “!” or won’t finish updating, contact Apple Support; an Apple Store can restore it with special tools.
HomePod mini can be restored from a Mac or PC: connect it with its USB-C cable, select it in Finder / Apple Devices / iTunes and click Restore HomePod. The computer downloads the right firmware automatically.
Apple TV with a USB-C or micro-USB port can be restored in Finder or iTunes the same way as an iPhone.

Signing

Like iPhone firmware, these files only install while Apple still signs them. The “Signed” label on each file shows the current status.

Apple Watch, HomePod and Apple TV updates (OTA files)

How to update normally

Restoring a device that won’t start

Signing

Devices that use this method