Magnetic field scanner
The iPhone magnetometer measures magnetic field strength. Findy compares what it reads against a baseline you set yourself, so you can investigate whether one specific object contains more hardware than it appears to.
The magnetic field scanner is free. No subscription is required.
What it measures
Electronics containing motors, speakers, shielding or magnets distort the magnetic field around them. Sweeping the phone slowly across one object, and comparing against a baseline taken away from electronics and metal, can reveal that an object is not as empty as it looks.
Findy reports deviation from your baseline. The baseline matters: take it away from electronics and metal so your readings mean something.
What it is for
Investigating one specific physical object you already have a reason to be curious about — a smoke detector that sits oddly, a decorative item facing the bed, a clock with no obvious purpose.
How to take a reading that means something
- Remove magnetic phone accessories, cases and stands. They dominate the reading.
- Establish a baseline well away from electronics, appliances and metal.
- Move slowly around the specific object you are inspecting.
- Repeat the measurement to check the reading is stable rather than a momentary spike.
- Compare several sides of the object rather than one face.
- Compare against a similar object elsewhere in the room, if there is one — two identical fittings should read alike.
- Inspect the object visually before concluding anything.
Reading a result
Within your baseline
No meaningful deviation at this position.
Deviation worth checking
The field near this object differs from your baseline. Something ferrous, magnetic or electronic is present.
Related
The guided inspection checklist tells you which objects are worth measuring in the first place. The Bluetooth scanner is the other free tool.
Last reviewed 2026-07-23 · Reviewed by the Findy team at Flaps Apps.