OpenUDID is a drop-in replacement for the deprecated uniqueIdentifier property of the UIDevice class on iOS (a.k.a. UDID) and otherwise is an industry-friendly equivalent for iOS and Android, and most recently Windows C# and Silverlight (see links above). Usage
Please find the following code for getting the iOS Mac Address. Importance : As UDID related methods are expired in iOS 5 onwards, I prefer to use MAC address. MAC Address are Unique for each device. Source of this code.