Dial a phone number with an access code programmatically in iOS

Question

How can I dial a phone number that includes a number and access code programmatically in iOS?

For example:

number: 900-3440-567
Access C

Answer 1

Using this user can redirect on Call and after the call he/she will automatically redirected to the app. It's working for me and sure about it.

if ([[device model] isEqualToString:@"iPhone"] ) {

    NSString *phoneNumber = [@"telprompt://" stringByAppendingString:cellNameStr];
    [[UIApplication sharedApplication] openURL:[NSURL URLWithString:phoneNumber]];

} else {

    UIAlertView *warning =[[UIAlertView alloc] initWithTitle:@"Alert" message:@"Your device doesn't support this feature." delegate:nil cancelButtonTitle:@"OK" otherButtonTitles:nil];

    [warning show];
}