Hi all.
I'm passing this on second hand as I have not updated my 4s to ios9.1 as
yet.
I'm told that in Settings/Cellular towards the end of the options, there is
a toggle option Data Assist which offers cellular assist if you have a bad
wifi connection, or none at all. If this option is turned on and you don't
have a generous data allowance, you could get a nasty surprise in the cost
of your calls.
