Control camera from another phone I have a phone on a camera stand. Is there any way to turn on and off recording from another phone?

I also want to trigger taking photographs.
You can do that using remote screen sharing apps like TeamViewer.
Install TeamViewer host app on the host phone(phone on the stand in this case). Log in to your teamviewer account and setup unattended access to the host. In this way there is no need to tap on the screen to allow access.Install Teamviewer app on the other phone.
Type the code from quicksupport app in TeamViewer app, you will get the display of that camera in another phone.. Now simply click the shutter button to click pics and record videos

Hope this helps
Enjoy!