If you have Android devices, this post is about an iOS-only app. Sorry 'bout that.
But, if you have iPhones or iPads, this is the app you have been looking for to play your music from phone or iPad to BT speakers/devices, Alexa, and Chromecast. Right now, the MusicStreamer app on my iPad is playing a 100-song
playlist of music from my home network NAS, to our Amazon Echo. I can even shuffle the playlist each time it is played. I can also set the app to use music from my WD My Passport Wireless drive to use when away from home; like on vacations, etc.
The app is made by the same company that makes the popular FileBrowser, and the two apps interface beautifully for even more features. When my new Google Home gets setup, I can use Chromecast to play my music to it with MusicStreamer. It only cost $3.99 for all your iOS devices. Skip the free, crippled demo version if you have a decent sized digital music collection.
So, without further ado, here is the product page info from the Stratospherix app maker's website.
https://www.stratospherix.com/products/musicstreamer/Let us know how you like it.