Frequently Asked Questions

Magnetometer X is an iOS app that turns your iPhone into a precision magnetic field measurement tool. It uses the built-in magnetometer sensor to detect, measure, and visualize magnetic fields in real time. Whether you're scanning walls for hidden studs and wiring, conducting scientific field surveys, or just exploring the magnetic world around you, Magnetometer X gives you three specialized modes tailored for different use cases.

Magnetometer X works on any iPhone or iPad running iOS 18 or later that has a built-in magnetometer sensor. If your device can run iOS 18, it almost certainly has the required hardware.

Yes. Every iPhone since the iPhone 3GS (2009) has included a three-axis magnetometer, originally added to support the Compass app. Magnetometer X uses this same sensor but provides far more detailed readings — including raw microtesla values across all three axes and real-time visualizations.

Just open the app and you're measuring immediately — no account or setup required. You'll start in Gauge Mode, which shows the total magnetic field strength on a dial. You can switch between modes using the drop-down menu at the top of the screen or through the Settings page.

Gauge Mode displays total magnetic field strength on a clear analog-style dial, similar to a speedometer. It's ideal when you need a quick, at-a-glance reading — for example, checking if a magnet is still strong, verifying that an area is magnetically quiet for sensitive equipment, or just exploring how the magnetic field changes as you move around a room.

Wall Scanner Mode is designed for practical detection tasks like finding studs, steel pipes, and other metallic objects behind drywall. As you move your phone across a surface, the graph will spike when the sensor detects a change in the magnetic field, helping you pinpoint anomalies behind the wall.

Scientific Mode provides the most detailed view of the magnetic field. It displays real-time graphs of all three magnetic field axes (X, Y, Z) along with the computed total magnitude. You can record data over time, export it as CSV for analysis, and optionally tag each data point with GPS coordinates. This mode is ideal for researchers, students, engineers, and hobbyists who need precise, loggable magnetic field data.

Switch to Wall Scanner Mode, then hold your iPhone flat against the wall. Slowly slide it horizontally across the surface. When you pass over a stud, you'll see the graph spike and hear audio and haptic feedback (if enabled). Mark the spot, then continue scanning to find the edges of the stud or the next stud over.

Magnetometer X can detect any object that produces or disturbs a magnetic field. Steel pipes, iron rebar, and steel conduit are easily detected. Copper wiring carrying AC current also produces a small alternating magnetic field that the sensor can pick up, though the signal is much weaker and requires slower, extremely close scanning — so it may not reliably detect wires behind a wall. Non-ferrous metals like aluminum, copper, gold, brass, and titanium produce little to no magnetic signature, and non-metallic materials like PVC pipe or wood will not be detected.

For many common tasks — hanging shelves, mounting a TV, locating large nails — Magnetometer X works very well and is always in your pocket. However, dedicated stud finders use different sensing technologies (capacitive or radar) that can detect wood studs directly, while Magnetometer X only detects the metal fasteners in them. For professional construction or deep-detection tasks, a dedicated tool may still be needed, but for everyday home projects Magnetometer X is a remarkably capable alternative.

Magnetometers detect magnetic fields, which are produced by ferromagnetic materials (iron, steel, nickel, cobalt) and active electrical currents. Objects made of aluminum, copper, wood, plastic, or glass won't produce a detectable magnetic signature on their own. So a steel screw will cause a clear spike, while an aluminum bracket in the same wall might not register at all.

Magnetometer X reads directly from your iPhone's built-in magnetometer hardware. The app doesn't add any filtering that would reduce accuracy — what you see is what the sensor reports. For relative measurements and detecting field changes (like finding hidden metal), this level of accuracy is excellent. For absolute calibrated measurements in a research setting, you may want to cross-reference with a dedicated fluxgate magnetometer.

Zero Calibration sets the current magnetic field reading as your baseline "zero" point. This is useful when you want to measure the change in field strength relative to a known environment rather than the absolute value. For example, zero-calibrate in the middle of a room, then scan toward a wall — now your readings show only the difference caused by objects in the wall, making small anomalies easier to spot.

Several things can affect readings:

• Nearby electronics (laptops, monitors, speakers) generate strong magnetic interference.
• Phone cases with magnetic clasps or MagSafe magnets can offset the sensor.
• Moving the phone too quickly can cause fluctuations — slow, steady motion gives the best results.
• The iPhone's magnetometer can occasionally need recalibration — try moving your phone in a figure-eight pattern a few times.

Magnetometer X supports three units of measurement: microtesla (µT), gauss (G), and milligauss (mG). You can switch between them in the app's settings. Microtesla is the standard SI unit, while gauss and milligauss are commonly used in industrial and paranormal investigation contexts.

In Scientific Mode, tap the record button to start logging. The app captures timestamped readings of all three axes plus the total magnitude at the sensor's sampling rate. Tap stop when you're done, and the recording is saved locally on your device. You can then share or export it as a CSV file.

Recordings are exported as CSV (comma-separated values) files, which can be opened in Excel, Google Sheets, Numbers, Python, MATLAB, or any data analysis tool. Each row contains a timestamp, X/Y/Z axis values, and the total magnitude. If GPS logging is enabled, latitude and longitude columns are also included.

Yes. When GPS logging is enabled, the app can continue recording magnetic field data in the background even with your phone screen turned off. This is useful for long-duration surveys where you want to conserve battery while collecting continuous measurements.

Yes. Go to Settings and enable "Include GPS Data in Logs." When active, each data point in your CSV export will include the latitude and longitude at the time of measurement. This is useful for mapping magnetic anomalies across an area — you can import the CSV into GIS software or plot it on a map. The app will request location permission when you enable this feature.

Magnetometer X can provide real-time audio tones and haptic vibrations that increase in intensity as the magnetic field strength grows. This is especially useful in Wall Scanner Mode — you can scan a wall by feel and sound without constantly watching the screen. Both audio and haptic feedback can be toggled independently by tapping the icons in the bottom area of the magnetometer screen.

No. Magnetometer X is designed with privacy first. All sensor processing happens locally on your device. We do not collect, transmit, or store any of your measurement data, location data, or personal information. There are no analytics SDKs, no tracking, and no ads. For full details, see our Privacy Policy.

Location permission is only requested if you enable the "Include GPS Data in Logs" option in Settings. It's used solely to tag your magnetic field recordings with geographic coordinates. If you don't need GPS-tagged data, you can decline the permission or leave the setting off — the app works fully without it.

Gauge Mode is completely free — download the app and start measuring magnetic fields right away at no cost. To unlock Wall Scanner Mode and Scientific Mode, there is a single one-time purchase. No subscriptions, no recurring fees, and no hidden costs. You pay once and get full access to all features plus future updates.

If you run into a problem or have a feature request, email us at magnetometerx-support@protoserve.net. Please include a description of the issue, your iPhone model, and your iOS version so we can help you as quickly as possible.