Korean iPhone in Europe
my Friend is at Korea And he wants me to buy iPhone 17. Is Korean iPhone compatible in Europe?
Since iOS is country specific, not all features might be supported.
iOS and iPadOS - Feature Availability - Apple
The built in hardware might not support all carriers, if it comes to 4G and 5G:
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 - Apple