A free program for Android, by palcoder.

This app is designed for users who want to create their own ringtone from mp3, ogg, flac or other audio files.

You can trim any part of the audio file you choose to make it shorter or longer. You can choose to add echo effects such as voice, acoustic echo, and so on.

You can set the delay time, which is the time it takes for the sound to travel from the speaker to the ear. You can choose from a list of sound effects such as bokeh, reverb, and so on.

This app is built using FFMPEG, which is a library that provides access to many audio formats such as mp3, ogg, flac, etc.