Install iOS 15.1 If You Want watchOS 8
If you want to use Apple's new watchOS 8 operating system on your Apple Watch, you'll need to download the iOS 15 update onto your iPhone.
watchOS 8 arrived alongside iOS 15 and the Apple Watch's new operating system comes with some intriguing new features.
If you want to use it on your Apple Watch, you can download it right now. That said, your iPhone has to be on iOS 15 for it to work.
For more on watchOS 8, check out Apple's guide.
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