If you’ve got an app for editing audio or video chances are that you’re going to want a selector control, and Apple has done a great job with the trim controls in their audio and video editing apps.
Here’s an open source trimmer control called RETrimControl by Roman Efimov that is styled after the iPhone Voice Memos app.
Just like the control in that app this control provides a selector with draggable edges and an indicator showing the current time selected by the control, and you can easily gather the selected start and end times and length of the audio.
Here’s an image of RETrimControl in action taken from the readme:
You can find RETrimControl on Github here.
A great selector control for any app with audio editing.