My apartment door buzzer calls my phone. Generally they don't even attempt to buzz me, and then make me pick it up on the other side of the city.

Very neat. I was hoping to unintrusively tinker with my buzzer in my condo, but I found that the wires coming out of the back of the device used some sort of signaling system, and I couldn't just use my own controller to switch on the door buzzer to let someone in from my phone.

I would suggest complaining to your local branch. You basically have proof that there was no genuine attempt at delivery. The driver will get in trouble.

Wow, cool. Where did you get that? Does it also have other features such as allowing you to talk to the person in front of the door?

There are interfaces for most common door buzzer systems. I have mine linked to my FritzBox, super nice if you're taking a bath and someone rings...

My landlord already had it installed when I moved in, but yes, I can talk to the person at the door and press 9 to buzz them in.