While development has focussed on the command-line interface, this is largely implemented as Blender plug-ins, and an interactive control panel could be created for Blender.
At the moment this is not seen as a high priority as the majority of people computing phonons are not Blender users already, and the Blender GUI has a steep learning curve. If this is a feature you would like to see (or to work on!) please comment on this Issue.
While development has focussed on the command-line interface, this is largely implemented as Blender plug-ins, and an interactive control panel could be created for Blender.
At the moment this is not seen as a high priority as the majority of people computing phonons are not Blender users already, and the Blender GUI has a steep learning curve. If this is a feature you would like to see (or to work on!) please comment on this Issue.