A free program for Android, by Dairy App Notes Audio Editor Voice Recorder.

Funny Voice Changer is a fun app to change your voice. It offers various effects, from changing the tone and volume to changing the pitch. It can also change the tone of the audio file. 

The app can also be used to make jokes or funny video recordings. You can also record your voice and apply various effects to it to make it sound like other people. You can also make fake video calls and voice messages.

This is a very easy-to-use app. All you need to do is select an audio file from your device, apply the effect you want, and then save the file.