Amarok
Amarok was a feature-rich database-oriented music player made using the aging KDE 4 application framework. It was never ported to the modern libraries. It is possible to start it on modern distributions as long as compatibility libraries are present but the results are not great. Running the latest 2.9.0 version, released March 2018, is totally hopeless on modern Linux distributions.
Features and usability
You can start Amarok and get a window with a player. You can click play and perhaps it will play, perhaps it will hang. Perhaps it hangs before you get to click play. You can re-start it and perhaps get into it's settings to try to get an idea if there is something you can configure to make it not hang.
We did attempt to do any investigation or debugging or anything like that in order to find out exactly why Amarok's plain broken. An educated guess would be that it is a result of Amarok using the obsolete KDE 4 application framework which, in theory, should work on a modern system with KDE 5 libraries and KDE 4 compatibility libraries.
Regardless of why and what happened the end-result is the same: Amarok is a broken useless piece of software and a complete waste of time.
Verdict and conclusion
Amarok was a great feature-rich music player back in 2010. There was a 2.8 release in 2013 and a 2.9 beta in 2015 with a 2.9.0 final released in 2018. Three years of (probably not) development since 2015 shouldn't have resulted in a totally broken unusable piece of software but that's what happened.
The Amarok website at https://amarok.kde.org/ does not state that it's abandoned or discontinued. It also doesn't say anything about any effort to port it to KDE 5. It is much likely fair to consider this player to be dead until or unless someone picks it up and decides to port it to modern KDE libraries.
Alternatives
Stand-alone music players:
| Program | rating | framework | music collection database |
|---|---|---|---|
| Audacious | 
|
Qt5 or GTK2 | 
|
| DeaDBeeF | 
|
GTK |
|
| Elisa |
|
Qt/KDE | 
|
| Exaile | 
|
GTK |
|
| GNOME Music | 
|
GTK/GNOME |
|
| Strawberry |
|
Qt |
|
| qmmp |
|
Qt |
|
discontinued / abandoned / bankrupt & finished: Clementine | Amarok
Music Player Daemon clients:
mpd is a database-oriented music player daemon which can be controlled by numerous front-end programs.
| Program | rating | framework | type |
|---|---|---|---|
| Cantata |
|
Qt | X11 |
| GMPC |
|
GTK | X11 |
| mpc |
|
Command-line | terminal |
| ncmpc | 
|
ncurses | terminal |
| xfmpc |
|
GTK/Xfce | X11 |
discontinued / abandoned / bankrupt & finished: Sonata | KMP | Glurp
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