For example, browsing 'by album' just adds unsightly [+] icons that are hard to hit with fat fingers on a touch screen. There should be a carousel of album art that you can swipe left or right! If there's no album art, just show a grey card and the first 10 letters of the artist's name in 8pt white letters. Once you select an album, you see the tracks on that album sorted by length, because radio edits are short and obviously the most popular tracks, so they should be on top. If you click shuffle, it will shuffle all of the tracks of the current artist (since we showed the artist's name, well the first 10 letters, so you should be a fan of all of their work). But you can also add tracks to a playlist (that's not shown), by long-pressing them. And to remove them, double tap. Everyone will try those gestures at some point in time, so it's easy to discover. Besides, they will both make a sound. Don't worry about it not being loud enough, the UI sounds will play at volume 10, and they will pause the track being played, so you don't miss anything. Playback controls are easy, just one button to play/pause/rewind (double tap)/fast forward (triple tap). And long press (10% longer than short press) to reset the playback position. Wait, we also need a control to record audio to reclaim the space being used by the mp3 currently playing, like dubbing over a tape, extra-long press will do that. Maybe that's hard to remember, so quadruple tap will also do. There should be incessant popups to remember to use the replaygain functionality, without explaining what it does (store the replaygain figures on a Google sheet, but not use them for playback yet, because the volume control uses the pinch zoom-in and pinch zoom-out gestures and we're unsure which gesture to use to enable/disable using replaygain)