Apple Watch Latest Serie?

Apple released Apple Watch 7 in October, so that is the latest series. There are different models with every watch series, from Aluminum watches, to Stainless Steel, Titanium and Designer models, and that accounts for cost differences. There are also differences between a GPS only watch and a watch which is GPS+ Cellular. The Cellular models, which permit you use cellular to receive and make calls without having your phone with you and require a cellular plan with your carrier, also cost more than a GPS only watch.

That is correct. In your country, you need to check with your cellular provider to see if they support cellular on Apple Watch. And if they do, make sure you buy the watch in your country as Apple Watches sold in other countries are often not compatible in different countries.

A GPS only model will work in any country because it requires a companion iPhone to be tied to. It cannot be used as a cellular watch, so there is no compatibility issues anywhere.

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