I know what chroma key is – Green Screen - chroma key Review

I know what chroma key is, that was not the question/problem. iPhone camera does not come on with your chroma screens. Unless I shrink my head smaller than my screen so I can place it behind me and video with a second device the app does not appear to work. Seems like I’m not the only one having this problem!!! Please explain how to use your app with my phone’s camera. Thanks.
Review by JeffFrmJoisey on Green Screen - chroma key.