Here is the piece of code which will give you all the info about device
NSLog(@"uniqueIdentifier: %@", [[UIDevice currentDevice] uniqueIdentifier]);
    NSLog(@"name: %@", [[UIDevice currentDevice] name]);
    NSLog(@"systemName: %@", [[UIDevice currentDevice] systemName]);
    NSLog(@"systemVersion: %@", [[UIDevice currentDevice] systemVersion]);
    NSLog(@"model: %@", [[UIDevice currentDevice] model]);
    NSLog(@"localizedModel: %@", [[UIDevice currentDevice] localizedModel]);
you can get here the version number.
But i will suggest you to go with checking that the phone supports mail composer,sms or not
like
Class messageClass = (NSClassFromString(@"MFMessageComposeViewController"));
if (messageClass != nil) {          
    // Check whether the current device is configured for sending SMS messages
    if ([messageClass canSendText])
    {
        MFMessageComposeViewController *msgpicker = [[MFMessageComposeViewController alloc] init];
        msgpicker.messageComposeDelegate = self;
        msgpicker.recipients = [NSArray arrayWithObject:[self.productInfoArray valueForKey:@"Phone"]]; // your recipient number or self for testing
        msgpicker.body = @"test from OS4";
        NSLog(@"chat view array  %@",[self.productInfoArray valueForKey:@"Phone"]);
        [self presentModalViewController:msgpicker animated:YES];
        [msgpicker release];
        NSLog(@"SMS fired");
    }
    else {      NSLog(@"chat view array  %@",[self.productInfoArray valueForKey:@"Phone"]);
        NSLog(@"Device not configured to send SMS.") ;
        UIAlertView *alert= [[UIAlertView alloc]initWithTitle:@"Status" message:@"Device not configured to send SMS." delegate:self cancelButtonTitle:@"OK" otherButtonTitles:@"cancel",nil];
        [alert show];
        [alert release];
    }
}
This will help to resolve your problem.
Happy Coding
Cheers................