If you're looking to use two phones as a security camera, there are a few things you need to do. First, you'll need to download a security camera app on both phones. Once the app is downloaded, open it and sign in with the same account on both devices. Next, you'll need to find a place to put one of the phones so that it can record video footage. This could be on a shelf, tripod or another phone stand. The second phone can be used as a viewfinder so you can see what's being recorded. To start recording, simply press the record button on both phones.