Build Mobile App

I am creating a floor game. The floor game will have Bluetooth ability and LED Lights. I need a mobile app, where users can access from the App Store, the App controls the functionality of the Floor Game. Meaning, I want users to be able click a timer within the app (15, 30, 60 sec) and after the timer is over one of the LED lights goes out/dark on the floor game. In addition I want the app to be able to access the music library on the users phone, so the users selects a song, chooses a time (15, 30 60 sec) and once the timer goes out the music stops and one of the LED lights goes out/dark at the same time. So ultimately the App controls the game, it's how users can play the floor game.