Magsense Pro: Stud Finder

Magsense turns your iPhone's magnetometer into a stud finder. Slide the phone flat across the wall: when it passes over a screw or nail in a stud, it buzzes, beeps and shows the peak. Free to use, with a one-time Pro upgrade.

THE SCANNER (FREE)
• Finds the screws and nails that hold drywall to the studs
• Haptics and an optional tone that rise as you get closer
• Live signal graph, so you can see the peak
• Shows where the sensor sits on your iPhone model
• Low, normal and high sensitivity
• Mark the spot with a pencil before you move on
• Also finds other iron and steel in the wall: steel pipes, steel conduit and metal studs

PRO: ONE PURCHASE, NO SUBSCRIPTION
• AR wall map: pin one or two pencil marks with the camera and see every stud on the wall
• Stud prediction: a 16" or 24" (400 or 600 mm) on-center grid calculated from your screws, or measured from two studs; any custom spacing works too
• Hang planner: place a TV, shelf or cabinet and see which screws land on studs
• Level line: a true horizontal line across the wall, with its height above the floor
• Blocking: mark screws in the horizontal pieces between studs, so they aren't counted as studs
• Ceilings and floors: map the joists the same way (turn it on in Settings)
• Save your walls, take a photo with the overlay and share the plan

GOOD TO KNOW
• Magsense detects iron and steel, not wood. It finds studs through the screws and nails in them, so it works best on drywall over wood or metal studs.
• Remove magnetic cases, wallets and MagSafe accessories while scanning.
• Magsense can't see copper or plastic pipes, or ordinary electrical cables. No signal doesn't mean nothing is there: always check before you drill.