There are some hidden features.
1. you can use zip files.
you can copy zip files from pc (using network or using iTunes) and unzip the files. press a zip file for 2 seconds.
2. you can transfer iPod music to normal mp3 files.
Small “iPod” letter will be shown for the song which is imported from iPod menu. press a iPod song for 2 seconds, Another mp3 file will be appeared (this has same name but “iPod” letter)
3. When I get on the subway, I set a timer in Donut Player. Cause I often forget to get off while I am googling. Donut will alarm for you.