This is not a library or any third party helper class.

This is intended to explain you the concept of multiple edits that you can make with AVMutableComposition class.

There are 3 options in this demo project:change speed,done,change url.

The "change speed" option doubles the speed of the video and plays the preview.

The "done" option exports the video.Also the url gets updated.

#If you try to change the speed of the video multiple times without exporting,it will not be played properly. #So you need to export a video before you can edit it again.You can watch the preview without exporting.But,to again perform a new edit option,you need to edit it. #To get an elaborated answer,check my answer at the below link: http://stackoverflow.com/questions/21589058/how-to-edit-avmutablecomposition-multiple-times/38931691#38931691