A friend of mine told me about this interesting company -
Nav4All - which turns your smart phone into a GPS. We have, I think, discussed this possibility here before, but now there is a real company that is able to use your cell phone, a bluetooth GPS mouse and the 2.5G or greater cellular network to give you directions on your phone.
Currently the service appears to be free (exclusive of purchasing the GPS device and cellular data bandwidth), but I'm sure that this will change once they have more than a handful of subscribers.
Assuming the service remains comparatively low cost this would seem to be a major threat to the GPS gadget manufacturers such as TomTom and Garmin since it offers the advantages of always being up to date and supporting all countries, as well as saving the need to buy yet another large LCD screen and learing how to use its interface.
