The only other watch app I've seen is Lyd for the apple watch.  Don't have an iPhone, so that's a none starter! 

Also, an advantage of the Galaxy is that it works without a phone having to be switched on. 

There are 3 or 4 Apps in the iOS App Store (attached), but I don’t possess a watch of any description to say if any of them work with stations/My Sonos tab.

To me it does not make much sense to have a radio URL in a Playlist because a radio URL is mostly a play forever event. Nothing in the Playlist beyond the radio station will play.

I suppose that there could be a case made for playing a few tracks before locking on to the radio URL. One such case would be to play a special wakeup track in an alarm, followed by the local news station.

Yes, for normal use.  But this is a special case.  I'd like to be able to use watch as an independent controller without having to fire up the S2 app just to start the stream.  

Having said that, I created a sonos playlist which appears in the S2 app but not on the watch app playlist category.  So maybe even the watch playlist is buggered in any case…

So, it looks like this has all been a bit of a wild goose chase.  I'll email the author again and see if he can figure something out. 

Thanks again for your suggestions.