You can use NSArray method 'stringWithFormat: ' to add two or more string variables into an array.
NSString *Name = @"India";
NSString *Code = @"+91";
NSMutableArray *countryObject = [[NSMutableArray alloc]init];
[countryObject addObject:[NSString stringWithFormat:@"%@ %@ %@", Name, @",", Code]];
and also you can see I am concating two strings separated with comma(,) because in future, we can split this string by comma(,) as needed.