How to Make an App That Can Talk on the Phone

I made this app called on mute which basically let's mute people so people cannot speak for whatever reason talk on the phone. I could just type and it would be sent to the other phone was just like a fun project is to try out this new APIYeah but it was like super helpful was impressive I was able to make it in a day but it was just nice Swift UI stuff that I had learned over the last year by just using Swift UI and then adding that specific API. In WWC 2021 Apple announced Shareplay which allows you to like watch Netflix together over face with someone who speaks into FaceTime call and through Shareplay it would send what that person is saying back to them