I heard about it, sent the text message, got a reply sending me to a web page for instructions - for iPhone only - it's not available on my new Samsung Galaxy Ace 4 that I only got from EE last month.
I have a bad signal at home and was happily using UMA on my Galaxy Mini 2 until I 'upgraded' phones, only to find the new one does not have UMA - none of the new phones do.
I have to go stand by a back of the house window to get calls on my mobile now, unless I use VOIP, which happily connects using 4G - phone calls don't use 4G I'm told, that's for data only.
Aint technology wunnerful !
Virgin Cable (100/6) + EE Mobile BB