Does US Apple Watch 10 series GPS + Cellular work in India?
Apple Watch 10 series GPS + Cellular bought in USA does Cellular works in India?
[Re-Titled by Moderator]
Since watchOS and iOS are country specific, not all features might be supported. In case of an Apple Watch 10 the O2 sensor will not work for models sold in the USA, for example.
watchOS - Feature Availability - Apple
iOS and iPadOS - Feature Availability - Apple
The built in hardware might not support all carriers, if it comes to LTE:
Have a look at this article:
Apple Watch - Carriers - Apple
iPhone - Supported 5G and LTE networks - Apple
And the warranty for your Apple Watch may also be restricted to the country of purchase. In case of a warranty claim, you will have to bring it back to the country of purchase. Apple does not ship internationally.
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Apple may restrict warranty service for hardware products to the country where Apple or its Authorized Distributors originally sold the device.
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copied from: Legal - Apple Watch Warranty US - Apple