For Android 4.4+ the app requires to have notification access enabled. Settings > Security > Notification access > enable.
This is also the most beautiful and customizable music widget out there!
In order the widget to recognize the player you need to start playback after the widget has been added.
SPECIAL THANKS to Alexander Woodblock for sharing his methods about the universal music controls.
If you have suggestions about design and new features, please send me an email at firstname.lastname@example.org