Large updates needed for 2008 MacBook Pro I keep at my Mum's place. I forgot to bring the Lumia 1520 with lots of data on its 3G/4G plan.
So I'm parked outside the Post Office, beside a public phone that incorporates a wireless hotspot. Data consumed here is automatically billed to & subtracted from my home broadband data allowance.
Very handy for travelling.
Users of this network who sign up for this "Telstra Air" service automatically emit both a Telstra Air & a Fon network wireless hotspot from their home routers for visitors to use. Such visitors also have to be Telstra Air/Fon subscribers. Hosts only supply the wifi connection, there's no extra data consumed. Data usage is at the visitors' expense.
One of Mum's neighbours is a Telstra Air user, but their network is just
a bit too far away to connect reliably, hence my visit to the public hotspot.