Phone cameras have come a long way over the years and you may find yourself wanting to use your iPhone's camera in Ecamm Live as a camera source. There are four great ways to do this.
One method is to share the device's screen while it's displaying an image from the camera. To do this, connect the iPhone or iPad to your Mac using the USB cable, and you'll see the device's screen show up as a camera source in Ecamm Live. Then, use an app such as Shoot - Clean Camera Feed ($2.99 USD) to put the device's camera on screen. See the guide linked below for set-up details.
Here's how you can get it all set up.
If your phone isn't showing up in Ecamm Live, review these steps here.