You can test your webcam online or using programs that come with Windows 10 or your Mac. You don't have to wait for a video call to find out there's a problem with your webcam - test it ahead of time.

You can turn on the camera on your Windows computer immediately using the built-in Camera app, or another app that uses it.

If your iPhone camera won't work, you may be able to easily solve it. Here are some quick fixes to try before contacting Apple.

First, open the Camera app and check by switching modes – Photo, Portrait, Video, and Zoom. Navigate through the 1x, 0.5x, ...