I owned an iPhone for about three years, and I spent a lot of that three years calling conference numbers. That entire time, I was really frustrated that I didn't have a way to dial a phone number, insert a pause, and then dial a passcode. I never actually checked to see if this was possible; if it's not apparent how to do something on the iPhone, then it's not possible, because they do such a good job with the user experience. Or so I thought...
I then upgraded to a droid and experienced the same lack of function. I set out to determine whether there is an app for this sort of thing; this sort of function is an ideal candidate for a droid app, whereas an iPhone app wouldn't be able to do this because you can't control an iPhone's dialing functionality.
I was a little surprised to find that my first Googling yielded paydirt. I clicked a link, and started to read an article and it turns out that this is not an app, it's actually built into the droid's dialing application. I was a little miffed because this feature was sitting there right under my nose, just hidden in such a way that unless you knew it was there you wouldn't look for it.
Then it occurred to me that the exact same feature could be hiding in the iPhone's dialer app as well. It turns out it was. Conveniently, because of the iPhone's great user experience, and their failure here to make it obvious how to do this, I don't really feel like I need to blame myself for this oversight.