You can validate email using the following objective c code-

-(BOOL)isValidEmail:(NSString
*)emailString
{
NSString
*filterString = @"^[A-Z0-9a-z\\._%+-]+@([A-Za-z0-9-]+\\.)+[A-Za-z]{2,4}$";
NSPredicate
*emailPredicate = [NSPredicate predicateWithFormat:@"SELF
MATCHES %@", filterString];
return
[emailPredicate evaluateWithObject:emailString];
}