I used to have a Samsung Galaxy s5, and I was perfectly content with the music player it came with. I switched to Motorola, and the Audify Music Player sucks. Whenever I do a system update, it deletes my playlists. I need a good alternative, please.
Musicolet, in the Google Play Store, works for me. It has a good clean interface, multiple customizable playlists, and even supports things like album art and lyrics.
Loving it so far. Thanks!
I use the media player in X-plore.
X-plore is a file manager with several other useful features. It opens zip and rar files, accesses cloud storage, image viewer, media player etc.
It gives my Android phone the same functionality as my PC.
The media player is very easy to use. Assuming you’ve organized your music into folders.
For example,
I have Merle Haggard, then subfolders album1,album2 disk1&disk2,album3.
I can select the root folder, Merle Haggard and the media player goes through each subfolder.
Or I can select a sub folder and play only that album.
I don’t use mp3 labels to organize music. I rarely mess with playlists. I just want a “stack” of albums to play. 
I use Rocket Player. My favorite feature are the dynamic, rule-based playlists. For example, I have a playlist that contains songs that haven’t been played in the past 90 days. When a song gets played, it automatically drops off the playlist for 90 days, so I’m always getting songs I haven’t heard in awhile. There may be other players with this feature though, it’s an older app and I haven’t looked lately. I also like the clean, customizable interface, and have it set up just the way I want it.
Folder Player. It ignores metatagging and plays whatever folder you point it at, with or without shuffle. Since I have all my music in folders for each artist with a folder for each album, this means I can transfer a shit ton of folders to my phone and play them either on endless shuffle of the topmost “Music” folder or play individual artists or albums. And after looking at the fucking hash other music players have made trying to display music based on shitty metatagging, this is pure peace and bliss. Plays everything too so I can go ahead and throw FLAC files on there without converting them to MP3.
Folder Player sounds a lot like the player that comes with X-plore. I prefer using FLAC whenever possible.
CD rippers are setup to properly name files by artist, track number, and song title.
Apps like Folder Player work well without the work of organizing by tags.