Your android camera streamed on your desktop: use as a source for OBS, or as a webcam with v4l2.
How it works
The app allows a user to choose a sensor and a resolution. From there it captures every frame as JPEG and push them to a connected http client as a MJPEG stream.
You can use that stream in OBS with the Media Source or the Browser (lower latency) source: (change ip to your phone’s)
Or you can pipe the stream into a virtual webcam compatible with most apps. On linux you would use v4l2 and ffmpeg. see bash script remoteCamClient for an example of how to set that up.
No official client yet, you have to DIY your way with the provided http MJPEG stream for now. Let me know your interest for a turnkey virtual webcam or OBS plugin.
There is already an alternative, Droidcam, but it is not free for HD resolution 720p+. Also Droidcam cannot use the telephoto lens on Samsung devices.
RemoteCam is an opensource alternative to Droidcam (but with <10% of its functionalities).