I’m not smart enough to create the app but I’ve often thought about how cool it would be to have the “insert tuning app here” receiving vehicle data form the “data out” feature in game to help offer tuning suggestions. The app could read real-time data to suggest camber, caster, tire psi, sway bar, springs, rebound/bump, etc. I could see where having the friction data captured real time along with using the tire temps/psi, suspension travel, lateral g’s could offer suggests to improve the vehicles handling.
By no means will this replace what we do today by driving the vehicle and feeling what it needs to make a corner faster or travel across rough terrain. But it could give you data to support those feelings.