Similarly, and multiplatforms, I recommend DroidCam (https://www.dev47apps.com/). The interface could use some polish but it works well on android/ios phones to Mac/Windows and Linux.

What's your lag with Droidcam?

My experience was a delay of half a second, making it unusable for live conferencing.

I use DroidCamX too, I don't have any noticeable delay but I have a fairly solid wireless setup (Unifi AP in the same room) and most of the time I just use the USB cable anyway so I can also keep the phone charging

I've used it wired via USB to Windows, and it was usable for live conferencing.

Similarly, I've used the 'NeuralCam Live' app that also turns an iphone into a webcam. It's free to use, with extra paid options too. The biggest downside is the lack of microphone support, which seems an odd omission.

I think the article is missing the obvious solution: if you can't buy a standalone webcam with as good image/sound quality as a phone, then use/make software that lets you use the phone hardware, there's no need to try to build your own camera.

I recently switched from Droidcam to Filmiic Pro (~$20), and it's pretty good.

Filmic Pro supports clean HDMI out from the rear facing cameras on iPhones and some Android phones. You do need a capture card, but if you have a Camlink or the no-name $20 USB capture card that EposVox did a positive review on, you're good to go.

On Android (I have a P20 Pro), I use a USB-C HDMI dongle meant for a Nintendo Switch, but it works with my phone plus it lets me charge the phone while using it.

Filmic also has a "remote" app (~$3, iirc) so if you have an extra mobile device, you can control the camera app remotely (since the phone you're using as a camera has its screen is pointing away from you).

That's a cool app! Thanks for mentioning it.

I did not realize that Corsair owns Elgato.

Their key light is also a good way to improve lighting.

Worth noting that this won’t work with FaceTime.

Good way to burn your battery.