FM Radio on HTC One Google Play Edition My HTC One has the capability to tune FM Radio stations.  

And the Standard Edition comes with an app for using it.

However, I can't find a way to use the FM Radio on a (non-rooted) Google Play Edition. Any ideas?

Running Android 4.4.2 ... if that matters.
I'll put this altogether here.

Google and some OEMs don't seem to be supporting FM anymore, as evident in the Nexus 4 and 5 not having any FM hardware built in. The Samsung Galaxy S4 also are carrying on this trend. The theory being that there are Internet raido services that can stream thousands of channels. Which doesn't suit everyone. The theory is that it saves space for the hardware and cost in manufacture.  Android forums discussion on the lack of FM on Nexus 5

 This XDA thread suggests it isn't possible however there are FM apps out there.  

 This is a very lowly reviwed FM app  on the Play Store that claims to use the tuner.  UPDATE: Does not work on HTC One. 

 This XDA thread has an attached apk for an FM tuner that MAY work. I have not tested, the usual warnings about unknown sources applies, of course. 

 Another XDA FM radio 

For rooted devices there is  one more here   

The one that is most recommended that I have found is  Spirit FM  which specifically states that No internet connection is required.

Try them out, see what works, and most of all be wary of permissions and apps you are not confident about.