How to add audio/music to a Legend?
Audio and music isn't one of the priority project but we're thinking about it. It would totally change the app system making it a bit more complex so we're not sure it's a direction we want to take for now.
If you are on iOS:
You can stitch your Legends together using our free iPhone app called Replay and with it you can add music!
Here's a quick guideline on how to do it: http://help.legend.im/article/66-step-6-combine-legend-and-replay
If you are on Android:
Know that we're working hard to Replay for Android :)