A lot of vibrations around. Some of them are good. Let’s look at the in detail
Vibrations and movement are around us. And android phones have accelerometers. And computing power. Let’s have some fun. We use accelerometer, FFT and some code to display results as waterfall. Color codes phase, amplitide codes energy for a frequency. Unfortunately, accelerometer sampling timing is not very precise - so it can not be used fo serious measurements. Nevertheless, you can clearly see some cool results when using this on a plane.