BTW the second comment seems to be posted by someone who never read the article.
I think johngenx was replying on of the comments on the article, not the article itself. Sometimes people depend on apps (like google maps) that use cellular data to display the map instead of storing the map data on the cellphone itself. I have a feeling that this is what has led to people getting the impression that they have to be within cell range.
My biggest issue with cellphones is operating them in a storm. While a good case can make the device fairly water resistant, cellphone touch screens generally stop operating once they get too wet. This is not a critical issue, and I have used mine in storms before; it's just a bit of a hassle.