There is a large and growing interest from you, users of Sleep as Android, in automatic fall asleep detection.
Sleep as Android does NOT offer automatic fall asleep detection.
What? Others do have it. Why not Sleep as Android?
The truth is, others do not have it. They claim it in their marketing materials, and they also trigger their sleep tracking at certain times. But more often than not, you are not really sleeping at those times.
Heck, you are often not even using the device.
Why is that?
To detect falling asleep reliably is a really tough task. There’s a reason why Apple currently makes big waves with their new detection mechanisms like trying to estimate your daily routine and detect your before-bed rituals like toothbrushing.
Because it is next to impossible to detect a sleeping person using just an accelerometer and/or heart beat sensor.
What are the issues?
A large problem is distinguishing between a sleeping person and a person lying in the bed calmly, but awake. For example, someone reading or doing something on a smartphone.
So what does Sleep as Android do?
We are actively researching bleeding edge methods that we could use or combine to reliably detect falling asleep.
So far, however, we didn’t find any method that would be good enough to be put in Sleep as Android. We do not want to employ any half-baked attempts at this. We have to be sure that what we implement actually works.