Features I would like to see, but that I'm not sure if feasible in the current iteration:
- Using the vol buttons for playback control (double click to skip? Hold to pause?)
- Supporting built-in headphone line controls (might need different hardware?)
- Charging LED or indicator to see if charging/charged when the screen is off
- More sophisticated gestures for the interface (long press, swipe from center to ring, double tap, etc)
- Equalizer settings (bass boost, etc. — might need DSP?)
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