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 Little Big Mobile:
Banner+ allows you to display SCROLLING MESSAGES and PHOTOS on an extremely realistic LED dot-matrix display using your iPhone/iPod touch or iPad.Use Banner+ when are at HOME, at EVENTS, on the BUS, TRAIN, CAR even or in a BAR - it looks great at night and can be seen from long distances.Banner+ has a boat-load of features including: Display up to 6 different message types:1. CUSTOM MESSAGE2. CURRENT TIME3. IPOD TRACK4. TWITTER FEED5. IMAGE/PHOTOGRAPH (taken from your device's camera or image gallery)6. CAMERA VISION (iOS 4.x - live video from your camera!) 45+ exciting THEMES including multi-coloured, rainbow, flags of the world and many animated themes. Choose from any of the FONTS available on your phone + a special HI-VISIBILITY bitmap font. You can also insert cool symbols into your messages such as . Fully customisable behaviour including: SCROLL SPEED, INVERT LEDs, MIRROR, BLINK, SHAKE to change theme, DISABLE SLEEP. Uses hardware accelerated graphics and advanced image processing techniques to convert photographs to an LED dot-matrix representation. Supports iPhone/iPhone 4 (retina display)/iPod touch and the iPad. For best results use Banner+ when it's dark and crank up the brightness of your device. You might also need to adjust the scroll speed and stand back to make your messages more readable.