Features
* The 'SETTINGS' tab is added.
* Background color of the playback control panel can be changed with
ColorPickerPreference open source library.
* Show licenses of open source libraries which are used in this app.
* Show version of this app.
Features
* Color of texts on the overlay panel can be changed by tapping a title
or an artist.

Improvements
* Icons in front of titles on the overlay list are deleted.