The phone was one of the first new additions I made to the game. This phone would be the main source of story telling, so the different events, main or random, would all be funneled through the phone. I would've loved to add characters the player could interact with and maybe some more cutscenes, but right now we're a one developer and one artist team so we made do with what we had.
I also wanted to make sure we had ways of bringing in player input. We started off by just making some on-screen UI that would show when it was time for the player to make a decision, but it always looked a little out of place. When we added the Computer, which we'll talk about later, I had to sort out how to allow the player to use their mouse to interact with WorldPanels. This took hours of troubleshooting, but when I was finally able to get it implemented, I switched the choice UI to display on the phones UI instead. This made making choices feel much more immersive. There are a ton of different choices you can make all resulting in different outcomes to your game, for better or for worse.