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 The Appstillery Ltd.:
MapMatcher London takes mapping to the next level, allowing you to explore the same area on up to four maps at a time on your iPad. As you move about one map, so the other maps all keep in sync.Ever wanted to compare two maps? Ever wondered how the city's landscape has changed throughout history? How the metro map compares to reality?MapMatcher uses MakkaMappa technology and is a great way to experience the amazing way that MakkaMappa can turn any image into a GPS map. You can even import maps you've made on MakkaMappa.com for free! Display up to four maps (including the satellite view) on the screen at once. 12 maps are built into the app. Download more maps for free. Find over 30 of London's most famous landmarks. See your own position on any of the maps. Import maps you've made on MakkaMappa for free.The maps that come with the app include: Central London Bus Routes London Underground, including a geographical version and a Zone 1 street map version London Underground in 1908 The Royal Wedding Route London in 1807 and 1901 Hand-drawn aerial view West End street map Theatres Tourist DestinationsWe will be adding more maps to the app and these will appear as free available downloads within the app.