Solution 1:

To find the country of the user's chosen language:

NSLocale *currentLocale = [NSLocale currentLocale];  // get the current locale.
NSString *countryCode = [currentLocale objectForKey:NSLocaleCountryCode];
// get country code, e.g. ES (Spain), FR (France), etc.

In Swift:

let currentLocale = NSLocale.currentLocale()
let countryCode = currentLocale.objectForKey(NSLocaleCountryCode) as? String

If you want to find the country code of the current timezone, see @chings228's answer.

If you want to find the country code of the device's physical location, you will need CoreLocation with reverse geocoding. See this question for detail: How can I get current location from user in iOS

Solution 2:

NSLocale *locale = [NSLocale currentLocale];
NSString *countryCode = [locale objectForKey: NSLocaleCountryCode];
NSString *country = [locale displayNameForKey: NSLocaleCountryCode value: countryCode];

Solution 3:

For devices with SIM card you can use this:

  CTTelephonyNetworkInfo * network_Info = [CTTelephonyNetworkInfo new];
  CTCarrier * carrier = network_Info.subscriberCellularProvider;
  NSString  * countryCode = [carrier.isoCountryCode uppercaseString];

Solution 4:

For Swift 4.0,

You can simply use

let countryCode = Locale.current.regionCode

print(countryCode)

Solution 5:

NSLocale *countryLocale = [NSLocale currentLocale];  
NSString *countryCode = [countryLocale objectForKey:NSLocaleCountryCode];
NSString *country = [countryLocale displayNameForKey:NSLocaleCountryCode value:countryCode];
NSLog(@"Country Code:%@ Name:%@", countryCode, country);
//Country Code:IN Name:India

Source Link.