Just reliably estimating body fat and muscle mass could already sell well with high-class fitness studios. Those already offer those scales with handheld probes as a feature, and those contraptions are horribly inaccurate. With this you not only get accurate estimates, you can also attribute them to your body parts.

"This month you gained 5% muscles mass in your upper arms, but lost 3% in your core muscles" "Body fat in your upper thighs reduced by 10%. You are on track to reach your goal in 6 months". It might be expensive, but there would be plenty of customers willing to pay for that

Then they can work on getting price down and accuracy up, both of which seem to be goals for the future