Perhaps we could learn the lesson from Google's Glass that people didn't like the notion of being recorded without knowing it was happening.
> The main critique of Google Glass wasn’t really that they looked stupid (although, to be clear, they did). People were kicked out of bars for wearing Glass because the device represented a form of ubiquitous recording. Glass was outfitted with a camera that the user could activate at any time
https://www.wired.com/story/google-glass-reasonable-expectat...
Apple decided to give people an indication of whether the people using this device could see them or not, in addition to adding a big button on the top of the device you have to press to take a picture or video.