RunKeeper Pro
If you enjoy walking, running or other activities that can be tracked via GPS - RunKeeper Pro should be on your iphone (or Android device).
It is feature packed, tracking all the vital stats in relation to pace/speed and distance. It will record both automated and manual activities of your choice and provide prompts on your progress throughout.
For workouts you can choose between programming your own or use one of those supplied.
One of the most useful features is being able to listen to music on a run (for those who wish to do so), and you can take phone calls and when finished the app will continue where you left off.
For those looking to socialise their progress - in-built Twitter and Facebook integration is included so you can post your workout results.
It is now iPhone 4 compatible and there is a feature reduced free version. It currently costs 5.99 GBP and 9.99 USD. Not the cheapest of iPhone applications however it replaces dedicated GPS devices costing hundreds.
