A free program for Android, by Stonekick.

Up Tempo: Pitch, Speed Changer is a music editor, audio speed changer, pitch-shifting app, and audio editor designed by musicians.

You can easily change the playback speed and pitch of audio files on your Android device either independently or at the same time.

This app is useful for creating fast songs, or those that need different tunings.

It can also be used as a music looper and audio editor, for changing the talking speed on voice notes and podcasts, or for making nightcore.

It can also be used to change the pitch and tempo of a song, in one fell swoop.

It is a very simple app, so even those with no knowledge of music theory can use it.