One of Backpacker Magazine’s blogs, The Daily Dirt, has been my favourite in recent weeks.
Here’s another interesting post:
… In a new 30-second spot, the familiar hands demonstrate apps to replace a compass, identify bird species, and spot poison ivy. Add those apps to the already impressive list including the Google Earth and GPS systems and you’ve got a handheld, do-just-about-anything, outdoor genius machine. …
Click PLAY or watch it on YouTube.
Daily Dirt – IPHONE APPS HIT THE TRAIL
Still, I’ll be taking my iTouch on the trail with me this season. Mainly for listening to Audiocasts and Audiobooks during the long nights in the tent.
Where I hike there’s no free WiFi. So many of the apps will not work since the Touch has not phone service.
besthike.com 
Well if your ipod touch is jailbroken you could pre-load it with Google maps and terrain maps as well Rick. 🙂