Google Play was perfect for playing the .mp3 files on my Android phone. No need for an internet connection. Then suddenly it was ripped away, and YouTube is n

Google Play was perfect for playing the .mp3 files on my Android phone. No need for an internet connection. Then suddenly it was ripped away, and YouTube is not remotely a replacement. I still haven't found an adequate replacement because I don't know how to search for the features that are important to me.