Depending on where we are touring, my wife and I sometimes bring a dedicated GPS. We used it extensively prior to the availability of smart phones. It is great for getting out of larger cities. In countries that have Google Map bike data, we found our phones are much easier to use, and are faster than a GPS unit. Once the route map is downloaded and saved the phone can be changed to "airplane" mode so you are not using relatively expensive data or incurring roaming charges. While Google Maps are not always reliable without a paper map verification, they will usually get you in and out of big cities just fine.

We use MapMyRide Maps for most route planning.