volunteer work this week in a county park to finalize one of the Conservation Board's first cell phone audio tours (read about it here). A few days later, my daughter and I tried the tour. You can see in the picture that she is skipping down the trail. You probably cannot tell that she is holding the telephone. She definitely enjoyed the audio tour, probably because no one was fighting with her over who gets to hold the telephone.
When the understory (as in poison ivy) is not conducive to geocaching (we scouted out a couple, including Firebrand), I still feel the need to get out into nature, either on a bike or on foot. With kids, I tend to stay on well-traveled trails, and a cell phone tour definitely added a new dimension and freshness to the usual trail. You can't change a trail, so I welcome the tours.
There are twenty stops on the tour we took. Depending on your background, some stops are more interesting than others, but all are worth a listen.