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 Park and Go Services Ltd.:
The Park and Go app allows you to pre-book airport parking at all the major UK airport from the convenience of your iPhone.We've designed it to be easy to make and retrieve your bookings for our airport parking products when you're on the go, even if you're on the way to the airport!The app even includes directions to all our car parks from your current location. For over 15 years we have been doing our best to bring you the most competitive prices for airport parking in the UK. By booking in advance you can save 's compared to the drive on rates at Manchester, Gatwick, Heathrow, Luton, Birmingham and many more airports around the UK. So when you book your airport parking with Park and Go you know your getting a good deal.