Ultra 2 SPO2 from England work in US
I really want a new Ultra 2 but only if SpO2 would work.
I live in US. If I buy one internationally and bring to US would the SpO2 work?
Apple Watch Ultra 2
Until Apple changes the software on other Apple Watches, that are sold outside the US., the O2 sensor will work on these watches, since the watchOS software is also country specific.
But, that also means, that some other features might not be available, that might work on Apple Watches that are sold in the US.
The built in hardware might also not support all carriers, if it comes to LTE:
Have a look at this article:
Apple Watch - Carriers - Apple
And the warranty for your Apple Watch may also be restricted to the country of purchase:
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IMPORTANT RESTRICTIONS
Apple may restrict warranty service for Apple Watch and Apple TV to countries where Apple or its Authorized Resellers sell the device.
With regard to iPad devices with cellular coverage and iPhone devices, the warranty provides service coverage in the European Economic Area (EEA) countries and Switzerland. Outside this region, service options may be limited due to technical issues outside of Apple control – for information relating to iPad devices with cellular coverage and iPhone devices please see www.apple.com/iphone/LTE/ and www.apple.com/ipad/LTE/.
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copied from: Apple One (1) Year Limited Warranty – (UK and Ireland)