I never really played with my Iphone that much, but i recently downloaded the Geocaching app since I enjoy that Hobby so much. Although I have not used it for geocaching yet, I do love the features the app has. it reads your position from the GPS, accesses the geocaching web site, and lets you see all the ones near your current location. then it shows you the way there. Once I test it out, I will let you know what I think.
Another favorite toy of mine is the WiFinder it comes in handy when you are in a public location looking for their hot spots. It’s also very fun to walk around and see how many people have routers that are just open. i never would have guessed there would be so many.
those are by far my favorite two so far.