Sigh, sadly it is missing on my phone. I 'suspect' it has something to do with my trip to the UK in February, as I had a UK SIM in my phone (dual sim) then and that seems to have changed a number of things that I am still discovering (took me a while to get iMessage working again, for example). I expect it vanished then, as it is likely not supported over there, and I have yet to discover how to reset things that changed... Oh, well, will keep plugging away at it.