This student plays mp3s of educational content in an app capable of slowing the speed of the audio. (Such as TapeMachine Recorder by Samalyze). I lock-screen my phone and listen while I drive or do mindless jobs at work. But we need a headset controller app so we can pause the audio without much fuss while we keep 'working', when the content is complex and requires 'digestion' before proceeding. Current headset controllers will not target such audio speed changing apps. The pairing of such two apps would go a long way in making mobile education possible for the large population of working students.