Alex, I have a Samsung Smart Watch, it links to the Samsung Health app on my phone. It does blood pressure (after you calibrate it with a blood pressure cuff). It also does ECG, which basically examines your wave form looking for irregularities like Arterial Fibulation (AF). It tracks all the usual stuff, like how far you walk each day, sleep quality duration, etc. Follow this link to learn all about the Oxymetre feature:
https://www.samsung.com/au/support/m...oxygen-levels/
. There is also a Samsung Smart Ring due out in July which will bring new features. I used to have Fitbit watches, which were great for activity but very poor on health stuff. I plan on getting the Samsung Ring once I find out how It will integrate with the watch. The Samsung Watch also connects to your phone via Bluetooth and can receive messages direct to your watch. Many other features. It is an Android type platform. If your using an Apple phone then there is an Apple Watch with similiar functionality.