How to add billing country to Google Analytics in iOS library
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I am a tracking a transaction using the GANTracker class from the Google Analytics SDK. I cannot figure out how to get it to set the Billing Country (utmtco). In the JS this seems to be a parameter, but there is nothing like this in the iOS library.

    - (BOOL)addTransaction:(NSString *)orderID
            totalPrice:(double)totalPrice
             storeName:(NSString *)storeName
              totalTax:(double)totalTax
          shippingCost:(double)shippingCost
             withError:(NSError **)error;

This is the closest I get. I have tried to set a custom variable utmtco like so:

    [[GANTracker sharedTracker] setCustomVariableAtIndex:1 name:@"utmtco" value:@"Country" withError:&error];

This does not seem to do anything however, as the call has utmtco as nothing.

Thanks