I didn’t even know this was a thing that was possible, let alone yet another, and Free!?

Thanks. I’ve been looking for something like this or some sort of sensor setup to do the same.

Thank you!

Sounds like an interesting story that I'm curious about... how did putting a strong magnet in the ground help you install your main water line?

I had the main rupture under my floor which is a concrete slab. so Instead of breaking the concrete I routed a new line from the outside directly to the back of my bathroom wall, where there was a small space behind the shower to access the plumbing. Luckily there was no concrete underneath the bathroom tub so I made a hole with a power washer and a very long extension wand for it, directly vertical. In this hole I put the strong neodymium magnet. Now from the outside I was able to locate exactly where my other hole was with my app. This way I was able to install a new main into my house with no damage to my structure.

Neat! Thanks for sharing!