A smaller size means that the app will take up less space on your Apple device. This leaves more space for other apps, as well as other data such as photos and music.
6.6MB(Basis Fitness & Sleep Tracker)
Bowflex Boost: 3.4MB
22. Monitors blood oxygenation levels
Your blood oxygen level is a measurement how much oxygen is reaching your muscles. It is important because low levels mean that you will become easily fatigued during exercise. The more exercise you do, the better your blood oxygen levels will become.
Basis Carbon Steel Edition
5% have it
23. Has social features
Friends using the same app can be integrated with your account, allowing you to compete with them. This increases your motivation and makes it more enjoyable.