Having set up a Plex server and SMB server on a Raspberry Pi, I was determined to find an app that allows both streaming from the smb share, as well as providing the ability to grab missing art, etc. This app does it all well, and IMO, it's not only the best app in the App Store, there's (sadly) nothing even close to being as polished and functional in the Play store for Android (there's an opportunity there). Well worth the money!
MusicStreamer is available for download on the iOS AppStore.
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