Your phone already uses its sensors more than you probably think. They count your steps, point maps in the right direction, adjust screen brightness, detect motion, and rotate the display when you turn the phone sideways. Phyphox is an open-source app that lets you use those sensors directly, so you can explore the world around you instead of only seeing the features they power.
Your phone has more sensors than you realize
It sees more of world than you do
Your phone is packed with sensors constantly measuring the surrounding environment. It can detect motion, rotation, sound, light, magnetic fields, location, and occasionally air pressure. With the right app, you can turn it into a portable physics laboratory.
One of my favorites is Phyphox. Phyphox, shorthand for “physical phone experiments,” is a free, open-source app developed at RWTH Aachen University. It can read and display information from your phone’s accelerometer, gyroscope, microphone, magnetometer, light sensor, GPS, and—if your phone has one—the barometer.
t graphs data in real-time, runs built-in analysis, and can export the data you collect as a CSV or Excel document for later use. If you’ve ever wanted to learn more about the physics of everyday objects and actions, it is a great place to start.
Phyphox turns your phone into a scientific instrument
See sounds as a graph
The microphone is a great place to start. Phyphox offers around ten audio experiments, from simple volume meters to full spectral analysis.
Open the waveform experiment and clap your hands. The clap appears as a sharp spike, showing you something visually that normally only lasts an instant. After that, you could try whistling or humming a steady note. The audio spectrum experiment breaks sound into component frequencies using a Fourier transform. That allows you to compare a low hum with a high whistle, see the harmonic overtones in a note, or chart how difficult it is to hold a steady pitch.
- Brand
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Google
- SoC
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Google Tensor G5
- Display
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6.3-inch Super Actua, 20:9
- RAM
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16 GB RAM
- Storage
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128 GB / 256 GB / 512 GB with Zoned UFS / 1 TB with Zoned UFS
- Battery
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4870mAh
The Pixel 10 Pro offers an upgrade over the base model with the powerful Google Tensor G5 chip, more RAM, and more storage (if you need it).
There’s also a precise pitch detector using autocorrelation (which can be used to tune a guitar), a sound-level meter that reads in actual decibels (at least as accurately as a phone can), and a tone generator that turns your phone into a signal source for testing how sound behaves in a room.
Measure motion you normally only feel
Motion is where phyphox obviously connects to features you probably already use daily. The accelerometer helps count steps, detect movement, and contribute to crash detection on phones with the feature.
Try recording in an elevator. As it starts, stops, and changes direction, the accelerometer captures the subtle shifts your body feels. If your phone has a barometer, you’ll also see air pressure change as you move between floors.
The accelerometer is what enables your phone to work as a pedometer—each footfall shows up as a distinct peak in the accelerometer data, and you can watch the algorithm distinguish real steps from noise.
You aren’t limited to detecting footsteps either. Between the gyroscope and the accelerometer, your phone can very accurately collect information about your motion regardless of what you’re doing. I was able to very obviously see an unbalanced load in my washing machine because of its motion; you’re only limited by your imagination.
Map magnets, light, and air pressure
There are several other interesting sensors available in your phone besides those used to measure motion. One interesting example comes from the magnetometer.
Open a magnetic field experiment and move your phone near a fridge magnet. The field strength rises and falls across all three axes. Move slowly around the magnet, and you start to see why textbook field-line diagrams are drawn the way they are—the data traces the same curves. If you have multiple magnets, you can use the “Absolute” tab to see which one has the strongest magnet.
Out of curiosity, I placed my phone on top of my microwave (not inside) to see if the phone could measure the activity of the magnetron that creates the microwaves. It was more sensitive than I expected—it even managed to pick up the way the magnetic field changes with time.
The barometer measures changes in air pressure. It can give you an elevation profile that is determined by measuring change in atmospheric density (and therefore pressure) as you go up and down hills. Alternatively, if you happen to know a thunderstorm will be rolling in, you can use it to measure the decrease in pressure that causes the formation of rain clouds and hurricanes.
Build your own experiments
Phyphox also makes it easier to put the data from your sensors (or experiments) to use. It can run a small web server on your phone, letting you start, stop, and monitor experiments from any browser on the same network—essential when the phone needs to sit undisturbed or be attached to something moving.
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Every experiment exports data in formats ready for Python, a spreadsheet, Excel, or any other analysis approach. If the built-in experiments don’t cover what you need, phyphox has an experiment editor that allows you to choose sensors, set sampling rates, and design the output layout. Custom experiments can be saved and then shared as XML files, making it easy for a teacher to design one and distribute it to a whole class.
Your phone is a scientific powerhouse
Phyphox proves that physics isn’t confined to a classroom. Our everyday world is littered with examples of physics in action that we often walk by without ever considering, and we have the ability to casually take measurements that would have made any scientist alive 120 years ago envious.
Even if you don’t use it every day, keep Phyphox on your phone and the next time you notice something interesting or odd, see what you can find out.
Stephan is the sports journalist for the Maple Grove Report.
