Thanks to https://alfred.camera/
Simple security at your fingertips.
Everyone deserves peace of mind, alfred made security easy and free for everyone.
Step1.
Install on two phones
Prepare two phones and install Alfred on both devices.
Step2.
Sign in with Gmail
Open Alfred on the two phones and sign in with the same Google account
Step3.
Enjoy Alfred
Set one phone as the Viewer and one as the Camera, and enjoy simple security.