You can access the current local information for the device using NSLocale.CurrentLocale or construct a specific locale passing a locale code, for example 'new NSLocale ("es_ES_PREEURO"). You can get a list of the available device locale identifiers using the static NSLocale.AvailableLocaleIdentifiers property.

Your application can be notified of changes in the system local by using the NSLocale.CurrentLocaleDidChangeNotification as the notification to monitor with Foundation.NSNotificationCenter.