how detect ios version

Following way we can detect iOS version 

   NSLog(@"[UIDevice currentDevice].systemName: %@",[UIDevice currentDevice].systemName);

    NSLog(@"[UIDevice currentDevice].systemVersion: %@",[UIDevice currentDevice].systemVersion);

    

    

    if ([[[UIDevice currentDevice] systemVersion] floatValue] < 7.0)

    {

       

        NSLog(@"older than iOS 7 code here");

    } else

    {

        

            NSLog(@"iOS 7 and above  code here");

    }