MY FIT can connect your smartphone to a bluetooth enabled scale allowing you to weigh keep track of all your vital statistics for example( Weight, BMl, Muscle, Water, Protein, Visceral Fat, Bone Mass etc.).
Now with (HealthKit) integration your fitness results are shared, allowing easy viewing alongside your other medical information in Apple's(Health) application.
You will be prompted to allow permission to be granted, or you can set this up at a later stage should you choose to enable it at a later stage through the (Sources) tab within the (Health) application requires iOS 8 or higher. iPhone 4S and above.