A free program for Android, by nobapp.

Sound Analyzer is a free tool for audio spectrum analysis and visualization.

You can change the display range by switching the horizontal axis between a logarithmic and a linear scale. You can also set the screen to auto-rotate by choosing a fixed angle, or you can choose a random angle.In addition, you can change the audio analysis parameters in real-time by using a slider or a list. Plus, you can save the current settings and use them as the default settings for the future.

There is no limit on the number of sound spectrums you can analyze. You will see the results of the analysis in real time.