Originally Posted by
corrado33
There are apps that allow you to download maps ahead of time so that you can track your ride without WIFI or cell service. I use one for hiking called MotionX GPS. It's not free, but it's only a few dollars to buy it outright, so it's not a huge investment. It seems to work very well.
EDIT: Downloading the maps ahead of time isn't a requirement, the GPS will still work, but if you get lost and want to use the GPS as a map you won't be able to do it if you haven't downloaded them already.
Runtastic Road Bike got it too. It will tell you how much space on the map it will take to save to phone. It looks like it download as "Open Street Map" or "Open Cycle Map".