Does iPhone 5 work with Apple Watch 3?
Does iPhone 5 work with Apple Watch 3 if no then which one
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Apple Watch
Apple Watch Series 3 (GPS) requires an iPhone 5s or later with iOS 11 or later. Apple Watch Series 3 (GPS + Cellular) requires an iPhone 6 or later with iOS 12 or later. Wireless service plan required for cellular service. Apple Watch and iPhone service provider must be the same. Not available with all service providers. Not all service providers support enterprise accounts or prepaid plans; check with your employer and service provider. Some legacy plans may not be compatible. Roaming is not available. Contact your service provider for more details.
†† We approximate your location from your Internet IP address by matching it to a geographic region or from the location entered during your previous visit to Apple.
Buy Apple Watch Series 3 - Apple
https://www.apple.com/shop/buy-watch/apple-watch-series-3
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Features are subject to change and may not be available in all regions or all languages. Requires iPhone 5 or later.
Apple Watch (1st generation)