The smartphone app "Presence" can turn your old smart phone into a camera viewable by another device, such as a tablet.
https://www.presencepro.com/
Since I started using a dot to practice with the ammo shortage, I've been setup considerably further away in my Dry Practice area, like 10 yards or more. But I can't easily see the target and would like to know what the dot is doing as I press the trigger, or at least have a better view.
I read about an idea to use an old smartphone as a camera and view it remotely. I found an app called "Presence" which does just that.
I've setup a Smartphone near my Dry Practice target covering the target, and my iPad where I am standing. Using this App, I can get a good view of the target and the reticle when I press the trigger.
To use this, you need a smartphone with a camera, and another iOS device (either iPad or phone) to show the image. Download the Presence app on both. Register for an account, then log in. You need to setup the camera on the device that will be near the image you want to show. Then display the camera on the other device.
Here's what the app looks like on my iPad. "21B64F" is the name of my smartphone.
In my case, both devices are on the same home wireless network. I have not tried this "online" with LTE or 4G/4G services but I would imagine it would work there also.
This might be useful at a range or other outdoor shooting session where you want to see the fall of shot without walking all the way to the target.