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 RADSense Software:
FREE During Launch - WallBooth for iOS WallBooth is the fastest and easiest way to share videos on Facebook with friends and family. Focusing on simplicity, it's a point-and-shoot video recording application that lets you quickly capture that memorable moment and instantly share on your wall, or any of your friend's wall.This app requires a Facebook AccountFEATURES Upload straight to Facebook. We do not store your videos. Edit your videos before posting Control Facebook post privacy mode (Public or Only Friends) Add your own custom message to your video post High quality video recording Support iOS 5 multi-tasking capability to upload video in the background. We do not upload your Address Book to the cloud like others. Watch videos on any device, smartphone, computer or tablet.To ensure high quality and fast uploads, only 30 seconds of video is allowedPlease send us feedback at firstname.lastname@example.org !