If you value your privacy you will find it useful as it upholds the user's privacy since all the information is stored within the application and is not accessible by any external network.
It has tools that help the users download and monitor their fitness over a long period of time to see they are making any progress.
It can connect to the Apple watch to enable you to monitor your fitness activities conveniently from your wrist.
It can connect to the Apple watch and the iPhone to enable you to follow your fitness activities from multiple devices.
It is only compatible with iOS devices which locks out Android users from accessing it.