Are you talking about the Sleep section of Apple's Health app? AutoSleep seems to track more data than that does. It estimates my deep sleep, takes into account my HRV and heart rate, and gives me a sleep rating for the night (e.g. 90 out of 100).

Apple's Health app just tracks total time spent asleep which ignores my heart rate. My heart rate is always much higher if I've drank alcohol or ate something too close to bedtime, which AutoSleep uses to determine that my sleep quality is lower.