Yeah, calories, heart rate, floors climbed, distance and steps is all on the home screen.
It also can alert you to phone calls and shows app notifications which I find really helpful. The app itself generates brilliant stats that I find fascinating (sleep, heart rate, exercise performance). I can understand why you think you could become obsessive over it - but has genuinely made me more in tune with my body and I’m very glad I bought it. Only downside is it’s a bit chunky.