Apple

I will be honest here and I might get downvoted to oblivion since this Apple Watch group. I used a Huawei band that is like $20 only then after that, a Huawei smart watch. Very straightforward, just wear and it will automatically track your sleep, Awake, Light, REM, Deep, etc. No complications! The battery lasts for more than 5 days. I recently upgraded to AW thinking that it could be better but to be honest, it's just basically the same. The Huawei has blood oxygen monitor too but my SE which is a bit more expensive than the Huawei doesn't. Going back to sleep monitoring, I found the Apple sleep monitoring too complicated, maybe because I came from something that doesn't require something like setting bedtime, sleep focus, and I even ended up getting a 3rd party app so I can track my naps. If you need sleep monitoring, maybe you need to look somewhere else. I am not saying Huawei because if you are in the US, then you might not have it but there are better sleep tracking watch out there for sure. I know some folks here are recommending Ultra but I don't see the point of spending almost a thousand dollars just to get extra days of battery life so you can track your sleep.