Inspired by radiotray, GNOME Radio is online radio streaming player with minimum interface possible, making it very straightforward to use. Supports most media formats (based on gstreamer libraries) and ASF, ASX, M3U, PLS, RAM playlist formats.
Use GNOME Shell extension website.
GStreamer should be installed in all Linux distributions.
Editing categories and channels is still work in progress (Channels tab in Preferences).
In the meantime you can set your channel list by editing ~/.gnome-radio@gnome-shell-exstensions.fffilo.github.com json file.
If file does not exist just start any premade channel and file will be created.