Vibrations FFT is a true vibration frequency spectrum analyzer using the built in accelerometers inside your android device.
Vibrations FFT visualizes current accelerometer sensor data performs a Fast Fourier Transformation (FFT) and displays the results in an histogram. The dominant frequency (peak of the histogram) is highlighted for every axis within Vibrations FFT. In the settings the accuracy of the FFT can be adjusted in a range from 0.0625 Hz - 1.0 Hz. Vibration measurement results are shown in a separate tab for each axis.

Warning: High accuracy of the FFT causes heavy load on the cpu. It may disturb the results of your vibration frequency measurement!