I tried a metal detector app on my smartphone… and it actually worked

Andrew Moore-Crispin • October 6, 2017

Your smartphone is a metal detector

Today I learned that modern smartphones make pretty good metal detectors.

I’m not suggesting you mount your smartphone to a stick and go sweeping the sands for buried loot. Instead, maybe just file this under “nice to know” and recall it should the need ever arise.

Here’s what happened.

The City of Toronto requires homeowners to have their water meters updated from the old cast brass analog dial sporting sort to a new digital “Smart Meter.”

Insert some joke about Rob Ford here. I’ve got nothing… but given that this was a plumbing project, there were definitely pipes and propane torches involved.

What could easily turn into a very long story made short, the installer needed to turn off the main water valve. That valve lives somewhere near the bottom of my driveway. The rub: The weather here has been less than pleasant and, despite my best shoveling efforts, the bottom of the driveway was a sheet of compacted snow and ice.

As we searched around, trying to chip up the ice on the driveway, said installer mentioned something about an app he’d heard about. One that turns your phone into a metal detector.

No way, said I.

Yes indeed, said he.

To the Play Store.

Firing up my newly installed Metal Detector app, I started sweeping my phone over the general vicinity of where I recall seeing the water valve in the warmer summer months.

After several broad passes, the on-screen meter spiked and my phone chirped as I narrowed in on something metallic, hidden beneath the snow and ice. I grabbed a chisel and went to work.

Sure enough, there it was: The main water shut off for my house.

I was surprised the metal detector app worked at all and very surprised that it worked so well.

Having had a smartphone since smartphones became a thing, it’s nice to still find the occasional surprise.

An app for every… application

When explaining the many benefits of having a smartphone to fence sitters, apps are the feature I call attention to. I suggest the unconvinced try thinking of it this way: If you can dream up a use for the tiny computer in your pocket, chances are you can find an app to do just that. No matter how niche the idea may seem, someone else has likely seen the need and made an app to fill it.

There are, after all, over 1 million apps in the Google Play Store.

If you have a hard time waking up in the morning. If you need to record measurements of a room before you go out furniture or hardware shopping. If you want to find out when the next bus is coming, how many hits your website is getting right this second or who’s knocking at your door, there’s an app to help.

Want to judge the size of a screw so you know whether to grab a #2 or #3 Phillips screwdriver? Or if the threaded metal slug you’re holding is a lag or carriage bolt?

Want to see if your current couch placement makes for a good Feng Shui flow in your home? Or if the plugin water fountain should go on the north or south side of the room?

Want to find a metal valve because the meter installer is here and needs to shut the water off so he can do the job he’s under contract by the city to complete but said valve is hidden and you can’t quite remember where the damned thing is but you really need to find out in a hurry though there’s no way even a heavy metal shovel is going to clear that solid sheet of compacted snow and ice?

Well.