OBS Camera app for an old iPhone 6s

OBS Studio allows you to do fancy things with cameras, web cams etc, graphic overlays, text, live computer screens etc which you can use in video conferencing apps like ZOOM, FaceTime etc.

The output from OBS Studio can be a virtual camera that shows as an available camera that any video conferencing program can use. 

If you have an old iPhone laying around, install the OBS Camera app which allows the old iPhone to be a very fancy webcam and video source for OBS Studio.

You wouldn't get much money selling an old iPhone 6s--so why not get the most out it. (A cheap webcam costs MORE than an old iPhone 6s)