This is the dynamo wheel, it is not much different to a standard hub, just a little bigger and heavier:
This is it connected to my old Nokia, I like the way the maps on Nokia have all the data on the phone, it cuts down the mobile data costs. I've got a newer phone now for SatNav, but it is still a Nokia.
Mind you I've just seen that you can download the Nokia maps for other phones, so I could download the maps to my Android phone.