As this app can read and utilize multiple media formats why not add an audio conversion tool embedded in the app? That could assist audiophiles in converting their media content to their desired format and bitrate. You could even allow the trial version of the app only to convert to say- .mp3 format maxing out a bitrate of say 96kbps. And even then only 10 files during the trial. The paid version would get access to all formats say to a max of 640 kbps. Please if you consider this feature to be implemented do consider the compact nature of your current release and try to maintain the apps' lightweight functionality. I think, going forward, this feature would open up a whole new class for this app further cementing it as the audio go to for Android.