Welcome to the wonderful world of Geocaching. I use iPhone 4S to cache (remarkably dead on) and use it to get the coords for hiding our caches as well. On the main page of the App where you select the "Find Nearby Geocaches" (in blue) it gives you the current location coords. Go to your GZ and let the phone/GPS settle for a few seconds. Take a screenshot of the page so you don't have to worry about writing down the coords. Then select any nearby cache and choose maps and put in the new coords into the "Add waypoint' option then select it as a target. Then follow and if it takes you right to GZ then your coords are spot on. I have done this couple times with great success. So it can be done with a phone. You still need to go home and log all the info to hiding on a computer..the app won't allow you to publish caches.