Originally Posted by
chiroptile
This option will not give you turn by turn directions, and you need to own the device and preferably have an unlimited data plan. That aside, I found the smart phone/google maps an invaluable reference tool on our tour, for riding in the states, anyway, though it worked in Canada, too..
If you've got a smart phone, or plan on getting one, that would be the most efficient option for all sorts of information/communication on tour, all in one gadget. Drawback is the limited battery life, but recharging in most of the US is just a matter of patience.