GPSRecorder

GPSRecorder turns your iPhone in a GPS recording device. Use it to record your walks, share them and geotag your pictures
GPSRecorder displays the compass if you have an iPhone 3GS or 4 so that you can instantly know all that is important about your position : both geolocation and direction/North. If you can connect to the internet, an instant map is also available to find where you are and browse.
You can afterwards review your previous tracks on your phone, including interactive map, distance and speed travelled, or export one as a gpx and a KML file for use with other software (GPX is lingua franca for Locations). You can use it with google earth to review your trails on the desktop. You can directly export to houdah gps on the mac to geotag a large amount of pictures rapidly.
Continued use of GPS running in the background can dramatically decrease battery life.