What are some alternatives?
When comparing Poweramp and Shuttle Music Player, you can also consider the following products
foobar2000 - An advanced freeware audio player for the Windows platform.
Musicolet Music Player - Musicolet is a small yet feature-rich offline Music Player for Android.
Winamp - Winamp is a media player that allows users to play multiple-file formats, arrange media in a varied file-management system, and play unique media with AAC encoding.
Pulsar Music Player - Pulsar is tiny, ad-free and full featured music player with material design.
AIMP - AIMP : Free Audio Player : Официальный сайт программы
Vanilla Music - Vanilla Music is a clean, simple and opensource music player for Android.