The "Download Now" link directs you to the iTunes App Store, where you must continue the download process. You must have iTunes installed in order to open the link, and you must have an active iTunes account to download the application. This download may not be available in some countries.
From Claire Holmes:
This is a fantastic calculator that helps you identify your race pace.With 4 event types from Sprint, Olympic, Half Ironman and Ironman, you can take full control of this calculator and adjust your personal pace for each discipline to get an accurate measure of your race pace.Turning the screen around details how your total race pace is determined.Use this calculator to help determine where you need to increase your pace and find out where your pace is spot-on.