Overview | Development
Phonon provides a Qt-style interface for audio and video. It is aimed at the average desktop application, whether that is a game that needs sound effects or a full-blown multimedia playback application like Amarok or Bangarang.
If you writing a Qt program and want audio or video playback, then Phonon is almost certainly the right choice for you. It provides an API that any Qt developer will be comfortable with, and uses the native multimedia frameworks on Windows and MacOS. On UNIX systems, where there is no one standard multimedia system, it offers GStreamer and VLC backends.
However, Phonon is not aimed at professional audio applications (in the style of Audacity, say). For these applications, you will probably want more control over the audio layer than Phonon will give you, and you should probably be using something like JACK.