New ON/OFF test: switch a device on and off twice next to your phone and see whether the magnetic reading changes. Results are saved to History.
EMF Detector reads your phone's magnetometer and shows the magnetic field around you in µT or mG: on a live gauge, as separate X, Y and Z axes, and over the last 24 hours.
START IN ONE TAP
Tap the gauge, or the green START button under it. The app first separates the phone's own magnetism from the field around you. While it says "Calibrating…", turn the phone slowly in a figure-8 for a few seconds; the live reading then appears and stays steadier while you tilt the phone. A short vibration confirms every start and stop.
TWO WAYS TO MEASURE
• Standard: a radial gauge with plain-language levels from "No EMF detected" upward. In Settings you can switch it to a Safety view that labels a reading as background, weak field, wiring detected or live wire (an estimate from field strength, not proof of a wire) and sets it against ICNIRP reference levels for the general public or for workers.
• Paranormal: records a quiet baseline first, then rates each spike against it on a five-step scale and marks it on a session timeline.
FIND THE SOURCE
The Source tab turns the reading into a warmer / colder hunt. Move the phone slowly around the room; the indicator shows whether the reading is rising or falling, and the X/Y/Z bars show the sensor's value on each axis.
KEEP A RECORD
• Measurement sessions are saved with their minimum, average and maximum
• A 7-day trend with insights, such as how a reading compares with your usual level
• Notes and favorites for each reading, plus a side-by-side compare view
• CSV export of your history, and share-as-image for the current reading
• A 24-hour exposure chart on the main screen
• Peak hold, and "Zero here" to re-learn the baseline in a new spot
• Calibration offset, µT or mG units, and a choice of reference levels
TIPS FOR A GOOD READING
1. Start away from speakers, magnetic cases and car mounts, and do the figure-8 until the number appears.
2. Hold the phone flat and sweep slowly, a few centimetres from the wall or appliance.
3. Watch for a rise against your starting level rather than one absolute number.
4. Tap "Zero here" when you move to a new room so the baseline is re-learned there.
FOR GHOST-HUNTING NIGHTS
Spirit Box turns the live field into pulses, vibration and spoken words. It is entertainment: field spikes come from wiring, motors, magnets and the phone itself, and no spirits are detected. A Halloween theme can be switched on in Settings.
HONEST TECH NOTE
A phone magnetometer measures static and slowly changing magnetic fields: steel, magnets, motors, transformers and wiring under load. It samples about ten times a second, so it cannot measure 50/60 Hz mains fields accurately, and it cannot detect radio frequency, Wi-Fi, 5G or radiation. It is not a certified safety instrument; use it to explore and compare readings around your home.
Made for curious people comparing readings around appliances and from room to room, and for paranormal investigators.
Ratings & Reviews
3.9
out of 5
9 Ratings
• New ON/OFF test on the Meter tab: keep the phone still next to a device and switch the device on and off twice when the app asks. The result shows how many µT the reading changed between ON and OFF, or "No clear change under these conditions." If the phone or the reading moved, it asks you to try again. Results are saved to History and included in Export CSV.
• The test compares magnetic readings only. It does not tell what caused a change and is not a health or safety measurement.
• In History, a single measurement’s own average was labeled "7d Avg". It is now labeled "avg value".
Version 1.0.37
The developer, Kyu-Hee Jang, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Used to Track You
The following data may be used to track you across apps and websites owned by other companies:
Identifiers
Usage Data
Data Not Linked to You
The following data may be collected but it is not linked to your identity:
Identifiers
Usage Data
Diagnostics
Privacy practices may vary, for example, based on the features you use or your age. Learn More
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
Seller
Kyu-Hee Jang
Size
55.3 MB
Category
Utilities
Compatibility
Requires iOS 16.4 or later.
iPhone Requires iOS 16.4 or later.
Mac Requires macOS 12.0 or later and a Mac with Apple M1 chip or later.