Wow such a polished piece of work. Well done! The art style, music and sound effects are all so good.
A minor complain: the button seems to be quite unresponsive when trying to "slam" it. You have to press it slowly and gently for it to work. You're probably using the "discrete" in for the Rigidbody settings, using "continuous" would make the physics work better in this case.
I did find a bug: one of my delivery didn't arrive. I pressed the button, the box disappeared but the delivery plane never appear. The box didn't respawn either. (Playing the APK version btw)