A Discreet Camera
Just like you can use your AirPods to listen in on conversations remotely, you can also use your Apple Watch to see what your iPhone sees. Just leave your iPhone somewhere and open the Camera app on your Apple Watch.
Using your Apple Watch you can snap a picture and set a three-second timer.
Force Touch the display to enable/disable the flash, switch between the front and rear cameras, and change other settings.
Keep in mind, the display on the iPhone will show the Camera app and, you must remain within wireless range.