NSLog([[UIDevice currentDevice] name]); // Name of the phone as named by user 

NSLog([[UIDevice currentDevice] uniqueIdentifier]); // A GUID like string 

NSLog([[UIDevice currentDevice] systemName]); // "iPhone OS" 

NSLog([[UIDevice currentDevice] systemVersion]); // "2.2.1" 

NSLog([[UIDevice currentDevice] model]); // "iPhone" on both devices 

NSLog([[UIDevice currentDevice] localizedModel]); // "iPhone" on both devices 

float version = [[[UIDevice currentDevice] systemVersion] floatValue]; 

if (version >= 4.0) 

{ 

// iPhone 4.0 code here 

}