Thank you to everyone who has responded so far and left supportive comments! Just wanted to respond to one particular comment here:
Potential to be much less expensive than investing in the Lionel or (soon to be gone?) MTH systems if it requires only accessory and switch modules and a smart device. Sort of like LionChief for switches and accessories.
Landsteiner hit the nail on the head. I am familiar with Lionel's Layout Control System. As far as I am aware, that requires a wifi connection and the Legacy Base to control switches and accessories. My idea was to cut out all of the extra components and give people direct control from their phones via Bluetooth. Very similar to how newer Lionel engines can be controlled with nothing more than a phone with the LionChief app.