A read-only music player for the files you already keep in Dropbox or Google Drive.
OwnMusic indexes a music folder in your own cloud storage and plays it on iPhone, Mac and Android:
gapless playback, ReplayGain, an equalizer, lossless formats, .m3u8 playlists, and
pinning albums for offline listening.
It never writes to your cloud storage and runs no server of its own. Everything stays on your device and in your account.