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 Binary Solo:
Guess What? is a fun word game that will turn your iPhone or iPod Touch into a party! If you've ever played games such as Taboo or Catchphrase, you and your friends will love Guess What? It is an explosion of fun!Guess What is a cross between word games such as Taboo and Hot Potato. Team up and take turns giving your friends clues to lead them to the secret phrase on screen. Once you do, quickly pass it off to the next player. Don't get caught with the device last! The team holding the device at the end of the round loses!Guess What? Lite is a self-contained experience! If you like Guess What? Lite, you'll love Guess What? It has a customizable options menu, many more phrases, and some gameplay improvements!