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 FS Digital:
Announcing the next addition to our popular iPhone app series: Invention a Day! Perfect for the local pub quiz, filling 5 minutes of downtime or annoying your mates with facts galore! An invention every day. See previous inventions to recap on their significance. Share with friends and family at the touch of a button! From the original use of gunpowder to the invention of the ball-point pen, you can expand your knowledge and share these newly found facts with your friends and family. Why not check out other apps in our iPhone app series: Daily Zen Enlightenment Daily Scripture (supported by Christian Aid) Daily Haiku