You can measure the vibration frequency of an object or a source using a smartphone or tablet with an internal accelerometer.

If you use a smartphone or tablet with Android operating system, you can download Vibrations FFT from the Google Play Store.

To measure the vibration frequency, you will need to adjust the frequency range of the accelerometer.

The accuracy of the measurement can be adjusted between 0.5 and 2 Hz.

After that, the measured values ​​will be displayed in an histogram. The peak of the histogram is highlighted for every axis.

The results will be shown in a separate tab for every axis.

To get a better view of the results, you can change the frequency range or use a different device.