I love the humor in this, it's very grounded in reality. Some of the funnier conversations where you can be a bit goofy remind me of some quirky friendships of my own. I think maybe some light music would help this along, and take down the sound of the dial tones. It's also a little tricky to read from the list of numbers and might be easy to accidentally redial or skip a number, so maybe like a bookmark or other kind of cursor? I absolutely love the concept!