Can we use Apple Watch sensors all day long with no limit?

I'm student from Korea. I'm interested in apple things.

I have several questions about Apple Watch sensors such as ECG(Electrocardiogram), Heart rate, Oxygen Saturation, breath rate, atrial fibrillation(afib) and so on.

First of all, Can I use these sensors all day long? with no limit?

I'm planning to develop some healthcare application using Apple Watch with sensors.

I can't find examples of using sensors 24/7.

And Second, If I can use the sensors all day long, can I execute the app in background?

Finally, If I can execute the app in background, can I activate the sensors in background?

Thank you for your help.

I have tried searching developer guide, and searching the GitHub.

For my experience with sensor data, you can really only get 24/7 sensors from SensorKit which requires a special entitlement and must be for medical research purposes. Even so, it strongly considers privacy in the output so some sensor data is generalized or anonymized to some degree. I think you may be able to fire the sensors in the background, but we haven't attempted to do so due to the multitude of limitations of what an app can do while backgrounded? So for our use case, we fire up sensors for active measurement of specific scenarios. And for other research use cases, we rely on SensorKit to provide a 24/7 picture of what is happening around the user.

Can we use Apple Watch sensors all day long with no limit?
 
 
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