I use Motion GPX on my Ipad, the only trick is to have a changing cord (that's plugged in and charging) for any time you want to use it over an hour.

What I like about it is you can record a track, then send it to a friend via email you can also download from a friend if they send you one, plus you can pre-download an area you know your going to before heading out when you have wi-fi and then you have a bunch of extra info but you haven't filled you device's memory up with areas you know you wont be in