Hi. On my Apple Watch Series 3, There is a new icon I can add to the control. I looks like the icon for the noise app. However, only Apple Watch Series 4 and above support the noise app so why would it appear on here? Tapping on it brings me to a blank screen that his a "Done" button on it. Pressing done brings me back to control center. This button appeared about accouple months ago and I removed it from the control center and ignored it but since I just joined the community I though might as well just ask.
on Apple Watch SE and Apple Watch Series 4 and later measures the ambient sound levels in your environment using the microphone and duration of exposure.