To change the country in which you will use your iPhone, you have to start the Settings app, choose the "General" item, select the "Language and Area" option, tap the "Area" item and finally choose the country you want.
Steps
Method 1 of 2: Change the Zone on iPhone
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Step 1. Launch the Settings app
The corresponding icon is placed directly on the Home of the device.
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Step 2. Choose the General item
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Step 3. Select the Language and Region option
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Step 4. Tap the Zone entry
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Step 5. Select the country you want to set
The date, time, number and currency formats will be changed according to your selection.
Method 2 of 2: Change the iTunes Store Zone
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Step 1. Launch the Settings app
If you want to change the country linked to your Apple ID, you will need to do it from the "iTunes Store and App Store" tab of the "Settings" menu. In order to change the country linked to your Apple ID, you will also need to have a payment method and a billing address that is active in the area you choose. Remember that the content you will have available will be linked to the selected country.
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Step 2. Select the iTunes Store and App Store option
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Step 3. Tap your Apple ID
It is displayed at the top of the screen.
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Step 4. Tap View Apple ID
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Step 5. Enter your security password if prompted
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Step 6. Tap the Country / Area option
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Step 7. Select the Change country or area item
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Step 8. Select the country you want
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Step 9. Press the Accept button relating to the terms and conditions of use of the service
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Step 10. At this point, press the Accept button again to confirm
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Step 11. Select the payment method you want to use
Remember that you will need to indicate a payment method that is valid and accepted in the country you have chosen.
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Step 12. Enter your payment information
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Step 13. Enter your billing address
Also in this case the address you enter must be related to the country you have chosen in the previous steps.