Lots of great apps have already been mentioned, but here's a few extras which I like (all free versions), not bushcraft as such, but they do enhance use of the phone:
-GTasks - synchronize Google Tasks with the Phone - I use these as a todo list and notes to remember
-FlashLight - use the camera's flash as a torch - dimable
-3GWatchdog - (by Richard Gruet - there are a few similar apps) - Track your use of 3g data, optionally alert before you reach your quota.
-ScreenKeeper - allows you to keep an app visable, ie don't activate the screen saver if I'm running a particular app (like google maps)
-Heavens Above - Track satellites, especially Iridium Flares (You can also run this from your PC, from their web site).
-Android Task manager - you can see what's actually running on the phone, and kill off things you don't want.
-File Widget - this allows me to put a file (for example a PDF) directly onto the phone's home page. This means that I don't have to open a PDF viewer and then choose the file I want open, its just 1 "click" to open the file.