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 Continental Tire The Americas:
Continental makes it easy for drivers of commercial vehicles to find the nearest authorized service provider when they need tire or emergency road service. Using your iPhone, the Conti Truck Tires Dealer Locator lets you find and call the dealers closest to your phones current GPS location, or based on a location that you specify. National account customers and ContiFleet members can also dial the TrukFix hotline for service. Its the fastest way to access the emergency tire and road service you count on, from Continental truck tires.