PitchScope

The pitch scope app measures sound taken from the microphone and displays its pitch(frequency), waveform, and spectrum in real time.  Use this app to analyze voices and instrument sounds.
For example, why do vowels U O A E I sound like U O A E I? You can see and check the waveform and spectrum of each vowel. Also, for example, if someone says “this guitar sounds brightly and that one sounds heavy”, what is the difference? When you have such a question, you can check it with this app. 

Pitch, Wave form and Spectrum charts

Pitch changes