Wouldn't have helped a bit in this case- AF447 was out of range of any sufficiently reliable radio tower. Satellite would be possible in theory but this would be prohibitively expensive.
One device in my pocket that does two things badly or two that do them well? It's a no-brainer if you ask me.One device in my pocket or two? It's a no-brainer if you ask me.
The herd instinct among economists makes sheep look like independent thinkers.